Both are good projects but to me the main difference is that the Waves team always overpromises and underdelivers to the point of being ridiculous. The Stratis team on the other hand always deliver as good or better as they promise without any unecessary hype.
They don't overpromise, all the stuff is delivered. Peoples are just not patient and want everything NOW.
Sasha is also doing a lot of stuff he's not speaking about ... like he did today:

Alexander Ivanov and the business ombudsman Boris Titov signed an agreement to establish business incubator on «People of Growth» platform that will help the real business to conduct ICO on the Waves platform.
About Boris Titov:
https://en.wikipedia.org/wiki/Boris_TitovAnd if you check this guy lasts posts:
https://bitcointalk.org/index.php?action=profile;u=230178;sa=showPostsYou'll see all the crazy amount of work he done the past week ...
Waves and Stratis are both different. Both are spectacular anyway.