I recommend that you choose a MIDI controller with 360º wheels, which will allow you to control parameters with a high range, so you can use limited travel faders with infinite travel wheels.
On the other hand, Arturia’s keyboard is fine, although its wheels are toy wheels (crap) even on its higher-end Keylab mkII keyboards (Arturia should copy Akai’s wheels). Most controllers add limited-turn wheels. I consider it a huge mistake.
61 keys is ideal. If you choose a 49 keyboard you will miss more octaves. It has happened to me.
Finally, if you want to experiment and expand the MIDI control of your keyboard controller, try this new tool: MIDI Universal Controller. The Arturia Keylab Essential 61-Key Keyboard would work perfect with this tool!