I haven't ever used a KeyStudio before but I presume it's a MIDI controller that'd work with any DAW. This answer assumes that is the case (the website seems to suggest this but I'm never quite sure.
Any DAW will be at least fairly complex. On the Mac, GarageBand seems to be a popular choice for starting out. It was my first real DAW, and through it I was able to figure out the basics of recording and eventually moved on to other software when I wanted more features. If there's a specific feature you're missing, it might be worth looking into what software has it, but if it's just that you aren't quite sure how to use Pro Tools, then switching software won't be nearly as effective as getting together with some like-minded friends and having someone teach you the ropes. If you have really specific questions, ask them on a site like this.
Judging by your comment, it sounds like the real problem is that you can't quite dial in the sound you want with the software instruments you have available. If that's it, then the real solution is to figure out what it is you want and then match that to a tool - in other words, find the right plugin for a job. Since I don't know anything about what you're trying to do I can only suggest that you find a community online that's dedicated to that style, and see what they recommend.
For general work I've never really found one major DAW to be far and away better than any other.