Our new 5th isn't too different from our old 5th. We started out as weekenders, then started week long trips, then now are doing 2 week trips (out west). Going west and being gone for 2 weeks, I wouldn't want a smaller trailer. We have room to pack everything we need and then some.
We also have room to spread out if we have a down day. Between the master bedroom, the big living room and the bunks, everyone can be apart. Sometimes I wish we could have it in a 28' package from a standpoint of site availability in National Parks, but we'd have to give up too much at that length.
If your kids are young, think about 3 or 4 years from now, especially if you intend to have the trailer then. Our old one had a bunk room with skinny bunks. It worked well for 8 years. In the 9th year, the kids were sleeping on the couch because the bunks were too small. In the 10th year we upgraded to the 29.5 BHDS and solved that issue. It will last us until the kids are gone.
2016 Jayco Eagle HT 29.5BHDS (ordered 12/30/15, delivered 3/8/16)
2015 F-350 crew cab, short bed, 6.7L PSD, Pullrite Superglide 3300 hitch