First, decide what look you want for your kitchen, you want smooth. Hard to get since wood moves, this includes the faceframes of cabinets if they are wood.
My sugestion is go to the local Cabinet company and talk with them about cabinets and designs. You do not have to use the company, just learn what you can from them about the differences in materials and looks.
Who knows , they may be cheaper than the box stores, and help you with your install to get started...if they want to sell you cabinets.
We always use quick clamps when screwing our cabs together as we work.
Keeps everything on the same plane...and smooth as possible.