"Regardless of how you fly though, the ease of use of software is a figure of absolute merit. I don't want to have to do 10 keystrokes to add a turnpoint sitting here in my living room if I don't have to, and there programs that do it with as little as one."

You cannot get away from the fact that different ways of flying tasks lead to different software designs. Where I fly, we always set up pre-determined tasks before going near the glide computer. On the glide computer, we never enter them via the map but always via a text based task entry routine. Both SeeYou Mobile and Winpilot are very good for this. If we change our task we have effectively abandoned the task, in which case most would use a simple Goto feature - which again both SYM and WP handle well.

I am running SYM on a GliderGuider, which I rate highly for the bright screen and the internal GPS which does not have the track smoothing issue. I changed to SYM from WP mainly because of the vastly better support. Folks complain about an inconsistent UI on SYM, but I find it pretty good, and certainly more consistent than WP. I have played with LK8000, but it seems less straightforward to me than SYM.