DOA tones down the execution difficulty because you need to adapt your combos constantly. The way how it's done is good. DOA's execution is by no means "unfair".
No matter what character you use, the execution is never overbearing to the point of being "unfair". Eliot's execution is nothing special. Phase-4 & Hayabusa are still harder than him. Perform a Mishima or Hwoarang in TTT2, then come back to DOA5LR to put things in perspective.
That's actually the same for me, and is the reason I prefer 3D fighters over 2D fighters. With that said, the execution difficulty in 3D fighters is fair.
In street fighter V their are multiple characters that can pull off big damage without doing a 20 hit combo Laura, necalli, r.mika and birdie can all do 6-9 hit combos that do just as much as those 15-22 hit combos Cammy and chun can do but the characters with lower combo numbers have fairly simple execution and it does take a whole bunch of canceling like cammy and chun