If that IS the case with WTA games, then it isn't a good game. For me the site is built to play to win, not to accumulate lots of points. You can, if you want, play WTA and play for draws in big value games and gather points. You can, if you want, play PPSC and grab SCs and and to your total. But neither approach is what the site should be able to encourage, which is risking everything and playing for the solo first and the draw if you have to. Lose everything in doing that? Get your 100 back again. No big deal... unless your target is to grab as many points as you can. Which tells me what? Doesn't tell me you're a good player; it tells me you'll settle.
There's something not quite right about the "get as much as you can then play in the big value games" thing, either. If you are going to learn to play Dip well, you need to be playing in a game where you can see it being played well. If that is the only way to play against better players, then new members have to play in the games where nearly every power suffers CD and communication is nearly worthless. I can see how new members with knowledge of the game would be turned off by that.
PPSC does produce skewed games. It's like playing in a tournament where Detour98F or some similar version is being used. You can tell the poor players - they're the ones scrabbling for as many SCs as possible. I doubt I'll play many PPSC games now I know what I'm looking for. And likening them to ftf games where you try and grab as many SCs as possible simply shows how hard it can be to get good ftf games (which is a shame).
For me, at least, if you want to play a good game of Dip, players take no notice of how many points they're accumulating and just get on with it, enjoying each game for what it is. Otherwise you get another variant of Dip: Metagame Dip. I'm not talking about team play I'm talking about games where players go into the game looking simply to up their points, and possibly going into it aiming to draw. It becomes about upping your points not about each game standing alone.
Tournaments are another issue. I love tournaments. If you want a good game, play in a tournament :P. The thing is, here, that means maintaining enough points for a certain period to be able to participate, and that, in turn, means having to play non-tournament games to accumulate points. If entry into tournament games was the bare minimum of points that would be a necessary compromise. TDs could select who they wanted to enter by other means than by setting high entry rates.
Having said all that, there's enough evidence here to suggest both PPSC and WTA have their place on site. As has been said, you can choose which you want to play generally (although not if you take over a CD power).
And finally, you will NEVER find a site where you can guarantee playing ONLY against great players. Neither by PBEM, human GM or automatic judges. This is internet Dip; there'll always be good a mixture of better and worse players, and there'll always be a mixture of those who are just trying it out and don't stay to finish a game. CDs won't be prevented by any system.