I have been asked this question many times over the years, and my answer has solidified into "whatever convention best describes my current hand best."
I have played so many conventions and treatments, that I can see costs and benefits with nearly all. So my solution is typically to accept whatever my partner feels comfortable with, and apply the nuances that come with those choices. Typically, for me, it is not any specific convention, but the system, how the pieces go together, and figuring out what the strengths and weaknesses of the system are.
My favorite system was based on a 16-18 NT, four-card majors and "action" two bids (all four suits were 9-12 and could be 1, 2 or 3 suited, but the opening suit had to be at least five cards in length). There were a lot of specialty bids that would not fit into other systems, but it was a system that created a lot of difficulty for opponents and fun to play.