I've used:
Various cheap 35mm-only enlargers
Beseler 23c (upto 120)
Beseler cb7 (4x5)
Chromega-B (basically omega b22 xl with color head)

Amongst those, the Omega is the easiest to use. It's very simple for a color head enlarger. All it's motions are manualy operated and very smooth.

The 4x5 enlargers might be motorized and have blowers running the cooling system, etc... Nice, but not quiet and relaxing.

I have not tried the other brands.

I would recommend you get the componon-s 80/4 lens for your 35mm and 120 (upto 6x6) needs.
Barring that, an El Nikkor or Rodenstock would both be very nice.

If you can manage to get an enlarger with a color head, you'll be all set for variable contrast paper without needing to work with filters.