Even the RTT raises stability and load concerns because the weight, while less than a slide in, is still high up. Like anything else, it's a compromise decision that has to be made when configuring the vehicle with the available space and the desired equipment.
Perhaps the best compromise I've seen is the vehicles 4XOverland has done on his vehicles. There are down sides to what he did.
Ronny Dahl just uses a tent that pretty much springs open when you unpack it if I understand his tent correctly.
Of course, their approaches are different because of the type of off road driving they do. Ronny likes to push things to the limit (and has been known to break things as a result). Ronny does have an off road trailer with a RTT on it for when he is camping with the family. Even then, he still runs his equipment pretty hard. 4XOverland is more of a tourer and thus more conservative in what he does. His latest land cruiser has, for all intents and purposes, a slide in but everything is still low as possible and is very minimal in many ways. He also basically ripped out the rear seats in the crew cab and installed a lot equipment in there as well. Since it's mostly just him or him and the wife or him and the daughter, it works.