Is 1.5-2.0ppg expected for a skilled player that is draft+?
You mean in his draft year+1?
It generally depends on the league. Most guys with top 6 upside (in terms of raw skill) will be putting up at least a PPG in the CHL their draft year, with allowances perhaps if they are on an unusually bad team, battling an injury, etc. You would ideally like to see them improve on their draft numbers every year thereafter.
Even guys with 3rd line skills can be putting up well over a PPG in the CHL by their draft year+2 due to simply being older (and thus more developed) than most of their competition. Someone like Bryan Bickell is a good example. Brouwer put up 102 points in 72 WHL games his draft year+2 (after putting up 47 points in 71 games his draft year+1), and I wouldn't necessarily call him a particularly "skilled" player.
If they are going from a junior league to the top men's league (in RUS/SWE/FIN), or the USHL to college, they could easily be under a PPG. Doesn't really mean that much since they're generally playing against much harder competition than someone the same age in the CHL.