Hi and welcome to the forum.
First decide the type of camper and truck you want before looking at specific brands.
You sound like someone who matches my truck / camper requirements - maybe not, but this is what I would consider - but there are many options out there and this is just one set of options:
You sound like you don't need a huge amount of living space (more of an outdoor person + dog), hence a slide with its extra space, but also weight, cost and often height is probably not for you (these campers often have basement storage - very nice, but makes the whole camper taller which compromises offroad ability).
If you want to drive offroad then you would benefit from a single-rear-wheel (SRW) truck with 4x4. Double-cabs give you extra space, but lengthen the wheel-base limiting offroad ability a bit. Personally I like a supercab - a bit more storage for things like hiking and climbing gear, spares, etc.
Gasoline or diesel is your choice - pluses and minuses in both camps.
I would get more truck than you think - i.e. I would get an F350 (1-ton) SRW or other-brand equivalent - gives you more options for which camper you want. It is too easy to underestimate the truck you need for a given size of camper.
You need to decide whether you want hard-side or pop-up. I've heard good things about some pop-ups in cold weather, so don't rule them out, but people who own them on this forum can give you their opinions.
All but the smallest campers have bathrooms. Bigger ones have a dry bath - separate shower from toilet, which is nice, but needs a bigger camper - consider if you need this.
Once you know the type and size of camper then you can consider whose brand you want.
I mentioned 'offroad' above, but remember that if you are just thinking of driving down a forestry track then almost any truck camper will be capable of that, including the really big ones - my suggestions above assume you want to go further offroad, maybe not extreme Jeep trails, but places where weight, height, width and clearance are a consideration.
Steve.