Warrior Adepts Add Ons

So with the addition of my commander and librarian, I think I have everything I need for a bare bones game. I picked up a Speeder on a whim last weekend so once that's done I'll be meandering down to the local GW store for a game.

Wheeeeee! Zoom! Pew! Pew!

Which brings me to add ons. 

I believe the Dreadnought counts as a heavy, so I don't think I need a Devastator yet, but I don't have anything in the way of heavy vehicles. The general go-to seems to be the Rhino, but there's a good number of tank variations that I may have to put a call out to see what would be the best initial investment. 

  

It probably comes down to play style now that I think about it. In general I like playing a mobile game (at least in video games), so who knows? I may end up treating the boys like White Scars and getting a shit load of speeders and motorcycles (my sister totally wants me to get the one with the side car). But if there are people reading this, what's your transport vehicle of choice and why?