I was faced with the same decision a year or so back. I play with a live rock band and we play covers from the 60s through to the present so I needed something that could provide the range of sounds that was needed for the songs yet I wasn't interested in techno and hiphop grooves simply because we don't play in those styles and even if we did we already have a live rhythm section. I ended up with a second hand Motif 6. Because the original Motif series has been replaced with the ES series I was able to find a used Motif in an affordable price range. You can find them now used for around $900. The Motif has good analog emulations plus it has sampling and sequencing which are always useful features for any style of music. It also provides some good realtime control of sounds like you were asking about. You can even add extra synth cards that provide new features and more polyphony if you want.

I did look at the Korg Triton LE which was the other keyboard in the price range I was looking at but the Motif had a much better keyboard feel.

Just my suggestion anyway. Sure the Motif does have a bunch of techno dance oriented grooves and patches but I just don't ever need to use them.