Would be amazed if we were anywhere near as dominant next season. Something that's easy to overlook is injuries; the past few season we've been hit pretty hard pretty often in key areas & it's shown - this season though I'd argue our 4 most important players to how we play are Sterling/Sane (providing our width) & De Bruyne/Silva (best players); yes they've had niggles but for the majority of the season we've had them available. I remember similar for Leicester with Mahrez/Vardy/Kante, and Chelsea last season.
Think we coped immensely well with the Mendy injury (props to Pep & Delph in my opinion). I expect we'll have a little more depth in those positions next season so we may be able to cope if one does get a bad injury.
In terms of which teams can compete:
Liverpool will have the best 11 outside of ourselves, with Keita coming into midfield; they'll be a keeper away from a great spine (Keeper-Van Dijk-Keita-Firmino with Salah/Mane). But again this season they've rarely had injury issues to key players, a bad injury for one of their front 3 would be pretty detrimental & you just need to look at their benches to see they lack depth - may be able to add some depth but would be difficult to add enough. On paper they should challenge, but so often they drop points against lower teams, can they change that habit? We'll see.
For United I just don't see it. I feel like they've overachieved this season, and when you see them play they're simply not as good as Spurs or Liverpool for me. They need new fullbacks, they need at least 1 centreback, need at least 1 centre-mid, likely need back-up for Matic, need some actual wingers rather than forcing Martial/Sanchez/Rashford into that position & then actually need to sort out their issues within the team (all the media stuff about Pogba/Martial etc.). It seems a huge overhaul job, both us & them had this overhaul to do, and it feels like we've almost completed ours & managed to win the title whilst doing so, whereas they've just reshuffled what needs doing & still have a lot to go.
Spurs I think it's tough for them. Some of their players have to be looking at Walker & thinking his wage went up & now he has 2 medals round his neck. Add onto that the lack of spending power, and seeming desire of Alderweireld to leave. They'll do great to hang onto Eriksen Kane & Son; it's hard to see them keeping their key players and managing to strengthen enough to close the gap.
Chelsea I think will be a big threat. We've seen time & again how much of an advantage being out of Europe can be for a league challenge. They forever have this habit of one good one bad season. Expect a change of manager & a strong title challenge. Squad definitely needs a revamp though, but it's got a solid basis if they keep key players which they usually seem to.
Arsenal... Never know with a new manager could give them a boost, got some decent players, but very hard to see them making a real challenge.