If its a 21, you might not see much more but as far as parts and upgrades available for the Berk, that'll be the way to go.
On the bigger boats with stock power they offten put pumps that were really good about getting the boat out of the hole.
The drake pump prebably does a good job of that .
I personally would buy everything I needed to do the swap and maybe even some wedges and a straight snoot and droop snoot and possibly machine the intakefor a shoe and ride plate while the boat still runs.
Run the pump for all its worth and when its time to go, it's time to go!
All the extra parts will aid you in getting optimal performance out of your set up.
When you have squeezed everything out of it you can, you can always sell off any extras you migh have layingaround.
Its not an odd boat so I'm sure someone with a really good running set up could get you started in the right direction right off the bat .
Before I forget, might wanna check on the size of the hole the drake intake is going to leave.
If it's bigger than the berk, you got glass issues also.
Hopefully thats not the issue but something to keep in mind.
-beerjet-