Drum sound really hurts badly when transposing. You either loose the punch or you get that "wonky" undefined sound. I use Logic as a DAW and it has qute good transposition algorithms. What also works well is the app Capo.
Developing a good quality transposition algorithm is not possible for me. The development effort would be much higher than all the time I put into Stage Traxx up to now so far. Therefore commercial algorithms are quite expensive. I got quotes starting in the 4-figure range. I don't make enough sales to justify such an expense.
But here is a recommendation for good quality customizable playbacks: http://karaoke-version.com
The offer individual playbacks where you can choose which tracks they should contain and also whether they should be transposed.