Minimum suspension mods for occasional use slide-in camper?

Your Gen1 would haul the camper better if you didn't need to take as many people (better payload). Your on the right track with airbags and sumo or timberne, maybe something to help with the sway.

Take a look at the Round the world Tacoma build, he put a flat bed with a four wheel camper on it, some of his suspension mods might give you some ideas.
https://www.tacomaworld.com/threads/driving-a-tacoma-around-the-world.585792/

 

Timbren is not the right choice, I always suggest them for occasional towing/hauling, they ride terrible when in constant contact.

Firestone airbags w/pump and gauge with rear hellwig sway bar is my typical suggestion for camper setups.

 

Plus one on the Firestone bags + pump setup. I’ve had my truck towing 8k. Don’t recommend it, but hey, farm life lol. Yeah, I agree with the other commenters… I’d really go to a half ton for that camper.

 

Roadmaster active suspension.I think it rides smoother than stock. Bolt on and zero Maintenance

 

Have a 2018 TRD sport. Went with OME 2” lift and level with hd springs. Also changed to 10 ply tires for the slide in. Slide in is an outlander xl 950 lbs.no problems so far and really good on logging roads for hunting season. Use spring loaded hold down bars over chains better on hiway I hope this helps.

 

I'm a highly active admin over on the Scout Campers FB Owners Group and the usual answer for someone with your use case is air bags and a nice bicycle pump. You should also look into upgrading to E-rated tires. They are stiffer and won't ride as nice, but at 30-35 pounds it's not too bad. But when loaded, you can air them up much higher (I run 60 front/ 65 rear) and you get far less wallowing around on the road, and much less lean in the corners. Steering is much tighter and altogether feels better.

The Timbrens and like products can really give you a harsh/jarring ride depending on how you use your truck.

My truck is mainly used for camper hauling duties now, so I went with a heavy duty leaf pack. But as it currently sits unloaded, I pretty much have a six inch lift in the rear and it rides like I don't have suspension, lol.

 

I’m no expert but I would look at some lighter camper options. GFC, Ovrlnd, Super Pacific, Tune Outdoor etc