I think you made your preference known with the floor plan if you want to eliminate the trailers with an overhead bunk. I would no longer even look at those.
I really like a slide, especially if I am going to spend very much time with the unit. Just my personal choice. A few rainy days make a trailer seem to shrink when you are in it a lot. Also I would go dual axle if the trailer weight does not exceed my limitations.
Be concerned about tongue weight. A trailer need about 10-15% of it's weight on the tongue to provide a stable pull. Make sure your tow vehicle can handle that much tongue weight of the trailer you select.
Buy a good hitch that integrates sway control into the hitch, Equalizer, Reese dual cam, or something like those. In my opinion they are much much better than using the friction sway control bars.
Don't rule out a used unit if you find one that has been taken care of. You can save money usually if you buy from an individual. You can get price guides online from nada or kbb websites.
These are just a few thoughts, I am sure more suggestions are coming. Good luck on your decision.