I would think you'd want to check out the Yamaha YC73 here, which has great organ (after the update), piano and EPs etc AND a decent palette of synth sounds, with pitch bend/mod sticks which the Nord doesn't have. Depending on how deep you need you synth to go, this one board might do it all for you. It also has excellent integration with Ipad if you want to add soft synths.
Personally I own an Electro 6 73 as bottom board (for piano/organ etc) and the MODX7 on top. It's a great combo. However, while the the Electro's synth/sample playback capabilites are limited and there's no pitch bend/mod, I do find a lot of the patches very useful. The Prophet A1 pad is as good as anything on the MODX. And via the Nord sound library I added ProjectSAM's Symphobia strings which are similarly as good as anything on the MODX, if not better. There's also a basic but welcome attack/release knob for the synth as well as a rudimentary velocity-controlled filter (so with the above Prophet sample, play soft and it's dark, hit it hard and it brightens up considerably). All this helps elevate it to above a mere 'sample player', if not quite a full-blown synth.