Look there is no one answer to your question because every situation is different depending on what type of truck, what tires you have (what ply) and camper you have and what's in it, where you go and what you do when you get there (your level of comfort and play). If your camper is designed to fit you truck, you probably can get by with not many changes-again depending on what's inside your camper etc. If you have a three way gas frig, you need to be fairly level to make things work, that's not a problem so much with a compression frig. If you cook inside it also helps to have the stove level. A level camper is easier to sleep in and hang about in. So once you figure out what you want, then you go from there. That is what your dealer is for and if you need specific help we all love to talk on this site and give our advise and there are lot's of threads that discuss various options and solutions.
So, for example, I have a 99 F150 61/2 foot bed 4x4 with the tail gate down, and a 05 Gramby FWC. Things worked okay, as long as I parked on level ground, the problems started when things were not level. My 3 way shut down and defrosted a couple of times before I figured out I had to do something. Solution number one get a set of levelers and I added a line level to my gear. Sometimes I had some really interesting leveling set ups.Yep it worked, but I'm, lazy, so I went down and had some air bags installed and added a hand tape to my gear. Sure that was great, putting air in and letting it out sort of leveled things up worked-but again I lazy. Then they started blowing out or I forgot to check the air gauge before I left for the field-no fun., sooo after several months of trying to make that set up work, I gave up and added Helwig super springs. it sort of helped but not enough. My Ford dealer suggested I go to a specialized shop that basically, converted my suspension from a 1/2 ton to a 3/4 ton. Problem solved. Me and my truck are happy.
So in answer to your question do it right the first time, and use your dealer and sites like this for ideas; or you can be like most of us and spend several years doing this and that, and then adding this and that, until you see the next thing you want and adding that-like solar- and getting to start all over again
! From back pack to having that dream machine-- will it ever end
! You may need to go from point "a" to point "b" and you need to be ready for it - right-buy tires that can do that rock crawling with, but good for normal driving too, be prepared is the motto of this site!
Enjoy
Smoke