If your looking at 21 foot I assume your looking at Bumper Pull Toy Haulers. I have had a bunch of Toy Haulers 5 to be exact. We learned something with each one.
A front bedroom is a big plus. If the bed is sideways instead of walk around it is a real pain to make. My wife hated it. Plus you will have to crawl over one another to get in and out. That said if you did go with a walk around bed they take up alot more room.
Your truck can handle a decent size Toy Hauler. You can go as long as you want as long as you stay under about 12,000 gross for your 3/4 ton truck.
Hauling Harley's you will want to think of ramp height. Too steep and you could high center going in and out. You will have to play games with raising the front of the trailer to lesson the ramp height.
Open floor plan or enclosed garage. For me I preferred the enclosed garage. The Bikes are tucked away when your traveling and you don't have to climb over them when you stop for the night. Plus you will have a place to store the bikes in bad weather. When the bikes are out the garage can be used for additional living space with drop down couches, tables, tv etc.
One example if you looking for a front walk around bedroom with a enclosed garage you will be looking at a 30' toy hauler. Sideways bed enclosed garage you would be looking at 25 to 27 foot Toy hauler.
My last Toy Hauler was a Work and Play 30WR. I would look at the Work and Play 30WR 30WRS 275ULSBS. These are low Heavy Duty Toy Haulers where the ramp height is not too tall...
A 30WR or WRS is 30' plus tongue so your looking at 36" total length. It's a big Toy Hauler. It will limit you on where you can park it. Alot of State Parks can't handle a trailer that long. So, you might find the 275ulsbs will be better..
I know these are not small and your looking for small. W&P has models that go all the way down to 18'....
http://www.alrvsales.com/rv/johnson+city+tn/forestriver+traveltrailer/1267/forest+river+work+and+play+30wrshttp://www.rvtrader.com/dealers/Dave-Arbogast-RV-731466/listing/2016-Forest-River-Work-and-Play-ULTRA-Lite-275ULSBS-115925548Good Luck..
