I tried to make ALL my suggestions mostly software ONLY...

OK, sure, an SSHD streaming ROM playback system would up the price, but look at the Kronos... It has one of those (and a whole lot more!) and is comparable in price to a T4.

Take a look at the price difference between Korg and Ketron (and older Roland) 76's compared to the 61 equivalents. Not exactly bank-breaking, either.

I think this thread has a LOT of great ideas that are little more than code. Much of it, not even new code. If Steve cares to look over this list, I am sure much of it could be introduced without tacking much onto the list price.