all of this is for blasters only, corrs/defenders/sentinels have some caveats here
with that said; yes there are many alternatives to ice, that may even better given certain contexts, ice is just really easy to get a lot of damage out of and is generally highly rated in all contexts.
you cant really go wrong with ice, but for other sets:
psi: arguably better than ice for large team environments, has fantastic burst damage, especially once the snipe changes go live, but your basic combo is will dom -> snipe -> tk blast (or strangler if you are /plant i suppose). because of the projectile travels times, all 3 attacks will hit at roughly the same time making it seem like 1 attack. you can imagine 2 or 3 psi blasters doing this at the same time would be rather scary burst damage, however the sustained damage isnt that high. once the the 3 hit combo is used, you are mostly waiting around for it to come back up
rad: might be top damage dealer with the snipe changes, not sure yet, but even now its definitely viable and does decent damage, its just outshone by ice atm a little bit. another thing to note is the animations dont feel as "smooth" as ice imo, but that may come down to preference
dark: king of 1v1's imo, you get a lot of utility between life drain and -tohit on every attack. you also get a nice hold that you can proc out. unfortunately on the current patch the snipe is rather useless, however i think its going to be amazing once the beta patch comes out, which will give a nice damage boost. the gist of the set is you trade some damage for some utility
fire: is a little weird, in large teams it lacks a lot of damage imo, but in small teams (think 2v2, 3v3 sort of thing) the extra damage you get from the DOTs adds up to quite a bit of offensive pressure, unfortunately the set is really hard to proc though, so you really want a hold from somewhere. strangler from /plant would be the best option, but if you have another secondary you can get char from fire mastery, or spirit shark jaws from leviathan and they kinda-sorta work. personally i run char and can do a pseudo snipe burst with char -> blaze -> blazing bolt for some burst, but its not as effective as psi
beam: kind of similar to fire but more up front damage/not as reliant on DOTs. probably better in smaller teams because the damage takes some time to ramp up due to needing to lead with disintegrate (no burst, but good damage tbh, it just all comes as DOTs) before you hit really hard with your other powers. it has a neat trick in that the snipe damage is REALLY delayed, so you can snipe -> lancer shot to have both hit at roughly the same time, and they both hit really hard which gives some viability to joining in on large team spikes. another thing to note is that piercing beam is bugged atm and does less damage than it should, if that ever gets fixed then it gives you a third high power attack (though with one hell of an animation time) that also does -res, which would be pretty nice i think
dual pistols: honestly i dont know a lot about this set, but someone is gonna get mad at me if i dont include it. the set does a tonne of damage tbh, but has a major drawback in the animation times are really long, so you spend half the time planted on the ground being an easy target
now ive said in a few places "good for 1v1" or "large teams" or w/e, but really all the sets listed are viable for everything atm, its just some are a little more optimised for one thing or the other. also there may be some other sets that are good and just not come to my mind as i write this... idk
tl;dr there are more options than ice ffs