A belated welcome to the world of sample libraries!😃
Personally, I use Sonar but it looks lke you're on a Mac and I don't think Cakewalk makes a version for Mac. Logic seems to be the go to DAW for Mac users but that doesn't mean you should jump the DP ship.
Again, I would work with what you have. Discover what limitations DP8 has and if they become intolerable to your work flow then consider something else. It could be that DP8 might actually have more than what you need but first let's see.
As for your question about articualations, I like keyswitching. I program the keyswitches into the MIDI in the Piano Roll view.
I've said this a thousand times on this forum before but I will say it again, never let the score dictate what articulations to use for the sonic realization of your score. The written score may say "Legato" but for some reason a combination of portatos, sustains and portamentos just work better.
Again, welcome to the world of sample libraries!😃