I'm not following the PL close enough so I can't comment on Moyes. Why do you think he's a bad replacement?
In my eyes it is a massive gamble. Moyes has no real big match experience, no great European experience (basically zero at CL level), no experience of working with big players. Moyes has never even won a trophy. There is the idea going around that he's done well at Everton on a small budget, but that doesn't really mean anything, because that doesn't always translate to doing well with a far bigger budget. I personally think Moyes lacks that sort of big manager personality to motivate and go with big players, it's not really an appointment that brings much enthusiasm. Moyes basically is an unknown quantity at the top level of management, which makes it ridiculous for a club like Man Utd to appoint him, because most big managers would jump at the chance of the Man Utd job, we don't need to be making risky appointments.
Only 11% of Man Utd fans have voted for Moyes as their pick for manager, so it would be nowhere near the popular choice (Mourinho 46%, Klopp 30%, Moyes is the 3rd most popular choice).
The main idea in support is he is a man that will provide long term stability like Fergie did (as opposed to the most popular choice Mourinho), but I personally think that is a load of rubbish. With the little support he has the fans will turn on him very quick if things start badly. You're not really guaranteed long term stability whoever you appoint in the modern day game, if Man Utd aren't challenging for the title next season, the fans will be calling for his head very quickly.