To anyone slagging off what they did at the Padres, explain one thing - how exactly are they worse off since he took over and then sold up than they were beforehand. My take on things...
1. They were bottom when he took over and when he left they were back at bottom.
2. in the period of ownership instead of being bottom every year like previously - their fans enjoyed at least 5 years that far exceeded what had come prior - including being in the baseball equivalent of the CL a few times and the final once.
3. When he took over they didn't own a stadium and had to rent from the American football team, when he left they had a custom built stadium which was one of the best of the league.
4. For all talks over him not being in long term - until his divorce they seem to have been ran well, after the divorce he became a 'distant owner' due to the need of him basically being forced to sell to satisfy the division of property laws in California, but he owned them for longer than Blue Bill has owned us for in terms of him not being in for a long haul...
5. In American sports if you aren't competing then it pays to be the worst team in the league as it rewards you with the best of the young players coming through the draft - so MANY clubs use a system where when they are bad they go whole hog and suck terribly as a way of trying to strengthen for the future. check out the NFL comedy that was the 'suck for luck' season, when the leagues worst teams actually had a race to have the leagues worst record in order to sign the stand-out player in the following seasons draft, to directly compare this to how they'd manage a team in a league with relegation is absurdly daft.
6. He gets a lot of stick for the people he sold the club to, these people were passed as fit owners by the leagues other owners, and fitted the model of being one of their boys club, the original people he tried to sell to got blocked due to them not being part of this circle jerk.
Good points (jump to the bottom for a TL;DR); re the difference between an owner investing in North American sports vs PL, investing in wages is severely limited in NA sports. NFL, NHL, and NBA have hard salary caps (upper limits on total squad wages), with some exceptions in the NBA. MLB uses a "luxury tax," so that teams spending over a certain value have some portion of revenue redistributed to the league. League TV revenue is fairly evenly spread, so income comes largely through merchandizing and gate receipts (to get above the league's base income).
Teams that aren't good "shed payroll" to save up for future years and expect that worse results in the standings (table) generate better draft picks for the farm system (academy, of sorts). In MLB, salaries are very much controlled by the club until a player reaches a certain tenure, so an experienced MLB veteran out of contract (free agent = bowman) can demand a salary many multiples higher than a slightly younger, but team-controlled, player. Plus, player contracts aren't re-negotiated when a player is traded (transferred), so if you sign a bad contract, you can't necessarily get another club to take the player. A team like San Diego would either need to invest multiple millions (run something like $25M-$50M above income per year) to jump-start competitivity in MLB to compete with the big-money clubs like the Dodgers and Yankees; it's really not feasible given the financial model of MLB. Many teams try to add the one special player, but when it doesn't work out it eats up payroll for a long time, and so they are forced to retool with younger players and a lower payroll.
TL;DR there's not enough similarity between MLB and PL to take Moores' tenure at the Padres and project what he might do at Everton. He got them a new stadium and seemed to be interested in the club before his divorce, and it's hard to say much more than that.