I'm 65 kg and learnt using the 1650 but on a big board - Naish crossover 120 at 7'4.
Would I definitely say go for the 2000? I would say it depends on how confident you are and how much experience you already have. I think the 2000 may become a 'big' or light wind foil option when you are over the learning curve. As you get better you can get more performance out of smaller foil so might prefer something smaller anyway, especially if your board isn't small or you have plenty of horsepower /wing.

If you have no experience of foiling, then the 2000 is probably the better option.