Has the Sirlin squad so brainwashed you that you believe that good execution is demonstrated only in combos? Execution is a factor in every blockstring, in every hitconfirm, in every reaction, in every jump, in every skillfully-timed airdash, in every just-barely-safe jump-in, and in every other time that your character has to move with any precision. Execution is a factor every time that a player has to bridge the gap between theory and action. Execution separates those who can react from those who can only act and those who have trained from those who are, through their own volition, entirely unable to implement the tactics and mindgames that they so deeply cherish. Execution is not nearly as irrelevant in high level play as many who don't have it will tell you that it is so it is not simply a barrier of entry so much as it is a demonstration of skill; the existence of the execution factor keeps fighting games about both the body and the mind and that will always make the playing field more exciting. Besides, removing execution won't level the playing field, it will just illegitimize those who used execution as a means of leveling the playing field for themselves; if you want a "level" playing field, play an easier game.
Also, as a Litchi player who can reliably do many of Blazblue's more difficult combos, I can tell you that I do not, in fact, have every good execution.