i'm a big fan of latias personally. just for the fact that it's a bulky levitating dragon it already has a ton of utility. the other levitating dragons are all too aggressive (latios, hydreigon, and flygon) and lack latias's great bulk, or its speed which is very solid by OU standards compared to many other dragons. i'm not much for subcm sets tbh, because i feel like too many moves are focused on sweeping and that makes it harder to pivot throughout the early game. granted, latias is without a doubt one of the best subCMers in existence, but that set's just not my style. i much prefer to use latias as a pivot with all those great dragon resistances that i can abuse.
as an aside with regards to politoed, you can definitely set up on most nonspecs variants; the ice beams don't hit you hard enough so you can start cming. 252+ ice beam hits you for min 40% so you can always take at least two hits unless you switched into the first one (in which case it's your responsibility to lure out one of toed's other moves, all of which latias will chuckle at). take the first hit (max 46%) and cm, and now politoed doesn't stand a great chance of killing you in another two ice beams (at +1 you take max 31% and you've got lefties recovery). you can start recover+cming your way to wreaking havoc which will definitely force toed out and can possibly end the game on the spot. ofc the greater concern is with being encored/perishsonged/toxic'd, all of which will usually force you out immediately, but usually if toed is carrying lefties it'll have at least one support move so it's hardly an impossibility to scout.
i tend to lean towards cm+reflect/roar when i run latias. you don't have substitute for setting up but you can still do so, and until then cm is just for abusing free turns unless you plan on going for the sweep. in addition if you get enough cms from free turns you can become a real challenge to take down. reflect/roar on the other hand have plenty of utility in the early and mid game compared to substitute, which i don't really like using if i expect to be forced out soon (i know it has plenty of utility even in those situations, i just don't really like it). then i run enough speed to outrun jolly terrakion (i don't see much benefit in running max speed; the only thing you outrun is HP fire lati@s in that case. i can beat espeon just by spamming attacks or cming up, and statistically i'll lose to gengar whose shadow ball 2hkos me slightly more often more than my dragon pulse 2hkos it; those are the only other 110s that matter. granted, you need a whopping 240 speed to outrun terrakion, so it's not like the extra 16 EVs are gonna make much difference anywhere else). right now i prefer reflect because of all the uturns flying around; even thundy-t's uturn hits latias for around 30% which admittedly does sting. moreover reflect can support your teammates if you're against something latias can't wall (ie if you're expecting a switch to a physical attacker who outspeeds you, the obvious move is to reflect on the switch and exit to a bulkier mon next turn). if you're going full stall roar is usually a worthy alternative, but i don't tend to go all the way into full stall
if you try to run stuff like specs latias or recover+3 attacks, you're straight up outclassed by latios who has plenty more power than you and the same speed tier. even cm+recover+2 attacks is done better by latios imo. it's for that reason that i don't waste my time on pure offensive sets; latias sucks at all of them compared to latios who has more immediate power and has an easier time forcing things out by virtue of offensive power. moreover those sets tend to ignore the real appeal of latias, which is its fabulous special defense. i personally see 4 viable moves for latias, besides dragon pulse and recover which you should basically always be running: substitute (which tends to be run alongside cm for obvious reasons), calm mind, roar and reflect. there are a few others but those tend to be the most useful options, unless you're aiming for something a bit more niche like dual screens. wish exists but i'm not into it on latias because its base HP has never really impressed me for the job; gimme blissey or vap any day. i find that it's generally a mistake to run two attacks on latias because the third support move is so useful, with the exception of psyshock which lets you win calm mind wars, notably against keldeo. if you start running stuff like hp fire + cm then suddenly latios starts outclassing you again because its power is higher and it has an easier time threatening stuff out.
anyway latias's issue is and always has been the variety of mons that counter it - strong pursuits, bulky steels that can set up, strong u-turns - but that's what teammates are for. when i use latias it's not about setting up or doing damage. it's about abusing dragon-type resistances (plus a fighting resistance and an immunity to ground) to outplay your opponent and win the pivoting game, and maybe sneak in a sweep at the end. many things counter you, but you counter many things as well, and as so many analyses say, it's all about playing to your strengths