If I remember right, no, just the two Tones. Mind you, there's a lot of layered Tones, so piano/strings is available as just the one (but no, you can edit it independently).

You DO have to make allowances for the fact that this is an $895 product, and the up to date equivalent of the PSR3k is $1700. How many keyboard Parts do you get on Yamaha's $900 arranger?

Yep, just the two. UPR, LWR (or layered).

Apples to apples, my friends.

Roland's E50 (currently available at @ $1400 from Sweetwater) does have two UPR Parts, a LWR and a MBASS.