I don't think I actually have a favourite deluxe in the original line, they were all decent but in my mind they were outshone by the larger toys, and even the smaller toys for value. It's one of the few times I can recall that Deluxes weren't the be all and end all of the line.
If I had to choose, I suppose it would be Tarantuals or Cheetor, but both always seemed quite flawed to me even without the cartoon influence. I always liked Manterror but never owned him.