Still lukewarm on Stryfe even after Carina Challenge
My opinion on Sentry improved post Hero challenge, but I still feel lukewarm about Stryfe.
A big reason I think is that Sentry made certain fights feel trivial once ramped up, while I never felt like Stryfe made anything feel trivial. He worked well, and when he crit (which didn't feel very often) there were big yellow numbers.
Part of that is even after he is ramped, he still requires SP1-SP2 looping for his crazy damage, as the AI can be remarkably passive to allow your shock to fall off (yes more pro players can maintain the shock and just SP2 spam, but Stryfe doesn't have any power gain mechanisms to make that feel like you're spamming SP2). And even then, for me at least, all that build up for non-critting SP2 is just a massive let down.
Meanwhile, Mister Sinister can just hit those same damage heights by spamming SP1 while laughing at full stunlock combos from the opponent, or Purgatory can quickly throw back to back SP2s once ramped up. So there never seemed to quite be the same "overwhelming sense of domination" from ramped Stryfe that I got from other ramp up champions.
Another weakness of his was confirmed for me too - he is easy to ramp up when you have access to parry heavy, and when the block/chip damage is low like in the Abyss (ie. easy to ramp up to 100 charges against Abyss Thing). But in most endgame type content, the chip damage is higher and you can't get away with parry heavy (imagine trying to ramp up against Tranquilize Necropolis path - not as safe).