Why a motorhome vs a trailer??

There is going to be pros and cons when you compare any two, or more, RVing styles. Only you can decide how much weight any of those particular pros or cons carry for your circumstance and personal preference. I might put much more emphasis/importance then you on any particular difference.
We bought a Class C as our first RV. We wanted a longer unit with more room then our Tahoe could tow. We opted for the Class C rather then switch to a more heavy duty vehicle. The first year we did not tow, and changed that the second year. It cost us about $3k for the Sterling All-Terrain tow bar, tow plates, an Invisibrake brake system and the wiring and installation of everything. We had the work done at our local Camping World and they were running an installation special pricing.
For us, the convenience of being able to have the bathroom, kitchen, TV's and the dinette for our grandkids to use in our travel vehicle was worth it. They travel with us frequently. They are ages 5 & 7. We also have frequently used our Class C for day trips to the beach, trips to weddings, shopping trips to the mall, tailgating, etc., etc..
We just traded our Class C for a Class A because DH and I will be now going south for a few months every winter and wanted more room up front. We can still sleep us in the bed, daughter & SIL in the sleeper sofa with the built-in air mattress and the grids in the dinette. No complaints from anyone after a fun Memorial weekend trip!
Good luck weighing your options. You're doing the best thing by listing them out, talking them through, rate each of them. But don't agonize over it. A few years down the road, your circumstance will alter and you will probably be making a change anyway. Dive in and start having fun and making memories!

1. Want to have the conveniences of home while going down the road.
2. Don't want to own a truck. Would have no use for it except to tow the trailer.
3. Want to own a small car for daily use. My Fit is perfect for daily use and for a toad.
4. Want to be able to tow a utility or vehicle trailer for some types of trips. Now that we have sold our old Jeep, it's just a utility trailer for model airplanes, etc.
5. Think an RV is less of a road hazard than towing a trailer. May be just my imagination, but it feels safer to me than having that big thing behind me.

Have never had a trailer. Never wanted a trailer. Have always had a self-enclosed RV sort of thing, different types at different times of my life for different purposes. Have never had the slightest desire to get rid of it and get a trailer.

DH did all the setup for towing the Fit. Yes, he's really handy at that sort of thing, but all told it cost less than $1500. And faced with a $5,000 price for getting it done, I'd figure out how to do it myself if I didn't have a talented DH. There was nothing mysterious about it - just some work.

With either one, it is important to drive conservatively, leave plenty of stopping room, and in general, just don't be in a hurry. Sometimes it seems that Real Men with their big, powerful diesel pickups lose sight of that.

Also, don't know why exactly, but we don't get the horrendous mileage that most C owners seem to. We generally get 12-14 mpg, just motoring along conservatively on flat land. Less in the mountains, of course.

We've had both and recently traded our Class C for a 33' TT, and are very happy so far. We did it for exactly the same reasons you mentioned. Having a truck to run around in is very important if you are not going somewhere just to use the facility. The MH's were easier to drive, especially our 24', but having transportation when you arrive at your destination makes up for it. I also had a tow dolly and towed our mini-van a few times behind the MH, but had to be careful not to get blocked in that you needed to backup, because that was another project.

Another plus for TT is less expensive insurance and registration...at least here in NY.

we have a TT and a truck to pull with. was going to get wife a little bigger trailer and we looked at some. Last year we had looked at MH's but like you said expensive. Found a nice TT made an offer went back and looked closer told them that I would need to change the amount offered as it needed too much to make ready. Never heard from them again! Was going to look at another wife said she wanted a MH so end of discussion. made several trip to look locally several to another town about 150 miles away. Found some told the dealer what we wanted ....NOTHING! Went to another dealer found one the ac was not good, told himn we were interested but not until ac fixed. Called back and said ac checked out good, no deal. Found one with diesel I liked it, wife said too short. Found another with diesel made offer looked closer reoffered (who ever had had lived in it and it had too many unkowns) no response. Finally looked at Craigslist. Found one 300 miles away made contact drove up made offer got it.

Now with all that said, I liked the trailer as I like my diesel PU! Wife actually likes the trailer just that it is NOT convenient when she want something/potty break etc. So you have a lot of the pros/cons nailed but then it will come down to actual preference. Lotsa nice used C's out there (I wanted/got a B+) and some really affordable, but you are looking at at least a 10+ yo vehicle in most cases. newer will run in $50K ranges but some new can be had pretty cheap on sales at dealers. Most on CL want new prices unless really wanting to get rid of. Ours came complete, rough terrain tow bar, all necessary components hoses, sewer hookups etc so I didnt really have to move anything from the TT. We are on 1st extended trip. Milage is in 8-9 mpg range, some issues I need to address when we get home personal preferences.

Any how we bought a car to tow, so that is an expected if you want to go anywhere easily. Small rv's are not in your future so yes a towd would be needed. Some C's and A's are to be had cheap, friend got a 2002 diesel pusher 40 ft long 90000miles for less than $30K. Gasser models can be cheaper in some places if willing to go with older model. check craigs list for some ideas.

Bottom line is really WHAT DO YOU WANT! What will make it easy for your family. We are enjoying the MH, As I said I liked the TT and truck but yes they require time to set up and go. The MH is much easier in that regard but I could do the TT almost as quick. We have jacks and slides, not on the TT but everything there was manaual hookups and back up etc. If you really want to know what would be better rent an rv for a weekend and see how it works out. I think you will be surprised. Tow cars can be gotten cheap and set up relatively inexpensively if you go MH depending what comes with it.

I would have considered a trailer but I do antique shows several times a year and need to pull an enclosed trailer. Can't tow a trailer with a trailer.

When we go on trips we take along the motorcycles on a open trailer. When we camp we take the canoe or kayaks and the motorcycles on the open trailer. Motorcycles would be a problem towing a TT. Would have to get a toy hauler and then we would not have as much living space and would have paid just about as much for the toy hauler as we did for out RV. If we bought a standard trailer we'd still have to get a pickup big enough to carry both Harleys and pull the trailer.

I've done both in the past. The plus for a motor home is I think it's easier to drive and park than towing a trailer of the same size. Only negative is not having the tow vehicle to drive around. Ours is 26.5' so it's not very hard to drive or find parking spaces.

I bought my first RV a year ago knowing nothing about motorhomes - a Class C Four Winds. I've but 7000 miles on it and like it fine but, if I had to do it over again, I would have bought a trailer for all the reasons you stated. Yes, I would also have had to buy a truck but I think it would have been worth it. It's a pain to rent a car and often there's not a car rental place within 25 miles of the RV park and/or they're not open when I need to pickup or return. I've been quoted up to $5K to have my car and MH set up to flat tow the car and I think that's way too much. I've also looked at aluminum trailers (car haulers) but they're also expensive.

So, in my opinion, got with the trailer.

Good luck.