It really isn't an either or question. It all depends on what you end up finding you like to do when it comes to camping. You have the group that always goes to places with full hookups. At the other extreme, you have those who never camp in any designated campground and strictly dry camp. How long you stay in any given spot also has a big impact. Some can go days on a couple batteries alone, while others can't get through a night.
Personally, I've always had at least 2 batteries on the RV's I've had with electrical systems. This worked for me to get through at least a 3 day weekend. Later on I added a couple 2000 watt inverter generators. I recommend the Champion inverter generators here as they are at least 90 percent of the quality of the high end units at roughly half the cost. For most part time RVers you should easily be able to get a decade or two in use from one before needing any major maintenance.
Finally, I personally really like solar, but have to admit it really isn't all that attractive from a cost perspective. I also always take a generator too for the times when the Solar just doesn't cut it. On the plus side, when it does work it's totally silent and self maintaining. You simply don't do anything but enjoy the camping trip.
Hit the road, get a few trips under your belt, and keep a notebook handy to right down what you forgot, or wish you had, and keep notes on stuff like how low your batteries got, how often they needed re-charge etc. on each of your trips. Over time as you determine your actual needs you'll be able to make the best choices for you and your style.