i dont know what you mean re wasted space.
best idea is to post a pic of how you want it.
the issue is when importing from bb it resets to default even tho one has the track heights set...
whereas if you lay out the song in rb all seems fine.

i would also talk to pg support.

only other option and youll have to do this for each bb import is after import set the tracks the way you want and save the song.
youll have to do this once per song.

answer me this what do you need in bb you cant get in rb ??

also you might want to post a wish in rb wishlist.
the problem for developers...and ive been one...is if the dev implemented all diverse user wishes that the exe would balloon.
so choices are made. cant keep everyone happy

thats all i got.

om

my songs....mixed for good earbuds...(fyi..my vocs on all songs..)
https://soundcloud.com/alfsongs
(90 songs created useing bb/rb)
(lots of tips of mine in pg tips forum.)