Go for the Triton if you can, obviously. The sampling & enhanced FX put it through the roof. Be wary of the touchscreen; it might be too awkward to use easily if you have big fingers like mine. They revamped it a bit from the Trinity version, making it more ergonomic to use.
Going for an X would surely be acceptable, although an N would be somewhat better, both offering 76-key models. All Korg synths sound good to me, but you CAN tell the X5 soundset from the higher-end 01/W set. Its a memory/price-point tradeoff. Even then, run an X5 through an exciter and you close the gap considerably.
Don't sweat on-board sequencers. They're always going to fall short of their software-based cousins, although Korg's are damn good. If you use your computer in your music, go with a good librarian (I'm partial to SoundDiver) & a modest sequencer. Those will let you get a better overall grip, SD circumvents the program/combi limitation by plucking individual things from its MUCH larger available database and you can maximize your 3.5 disks by setting them up with the high-octane system and porting them over to the Korg.
If you don't, simply take the time to shuffle your data. Its not at all hard to whittle things down to 5-6 disks that cover 95% of the bases. I can play for a couple of hours with these 3 disks I massaged carefully.
Almost any wavetable-type synth SHOULD give you all the tools you need for a monstrous piano and any kind of Hammond you want. Sometimes the piano waves are wonky, but Korg's are winners. Double the piano octaves, balance their relative volumes and add in a bit of moderately crisp string section for a rockin' beast with oomph to spare. You can get a solid sound suitable for everything but Rachmaninoff, because those huge glissandos will choke most synths.
Program several B3s side by side and use the joystick/wheels or assigned pedal to adjust yer Leslie live. Live with the lack of proper drawbars in favor of all the other things the synth gives you. I know that's somewhat weird; I've played a B3 and its another world, but we ARE talking about useful tradeoffs.
The 01/Wfd might be a bit long in the tooth for you, but in my opinion, it was the first synth to get the M1 idea right across the board. They run about $1000-1200 2nd-hand now and they pop up here & there.
If you become a mega-star, you owe me a good pitch-shifter for my trouble. Hotcha!