We bought one without a slide. Although it was not a bunkhouse. Our floor plan is very roomy for what it is and we weigh about 6500-7000 lbs loaded.
Don't worry too much about the structural integrity of the slide models, they are just as bad without slides as they are with (slight exaggeration, but slide technology has come a long way in the 25 years that they have been making them.
We have two sons and there are times when we are stepping all over each other. On of the reasons we didn't get a bunkhouse model is because we found that without a slide out there was very little living room in the trailer.
When we buy another trailer it will have ar least a sofa slide out, more than likely it will be a superslide in the living room and a slide in the bunkhouse room.... Maybe two.
As far as quad bunk houses without slides. They made several models like that from around 2000- 2008 ish. There are several nice examples on the used market.
Good luck