All your examples are shit. But you're right that dota has longer duration CC, there's no question about that, it punishes bad positionning. It's also mostly countered by BKB as an item. Or by force staff. Or by support abilities. Or by proper timing of certain abilities. Basically, by playing better as a team.
On your examples, Naix slow lasts 8secs but only starts at 70% then is reduced by 10% per sec over the duration. It is also just a slow, on a melee hero that has no gap closing ability. Know a champion that's just like that in lol(or was last time I played), Olaf. Spammable slow with the axes, cannot be CCed, no gap closer. Granted the axes are a skillshot omg so hard to land. Only that if you land them once, then you have perma slow at full strength, and they have much much better range than open wounds has(even at max rank, at rank1 it's actually pretty much a melee range spell).
Naga Siren song is an invuln mez. You mez everything, but they are invulnerable to everything for the duration. It lets you position and time some abilities to hit at the end of the song, IF you time them correctly(and in this case direct targetted abilities are worse since you can't bypass the cast point by casting before the song ends). The song itself has a cast point of about half a second to make things harder. Her net is an immobilize, you can cast spells or attack while netted, it has some good uses, mostly the fact it's physical so it goes through magic immunity, but that also makes it counterable by a cheaper item than bkb, ghost scepter. Can still force staff away with it on. As most projectiles, it can be dodged by disjointing it with a timely usage of blink, invis, banish or manta style.
Your assessments are flawed which is why no one bothered answering to you. The whole skillshots argument is, as I said, retarded. A hero doesn't require skill if she has only one skillshot and not 4? What about invoker then, he has 6skillshots and 10spells. Meepo is up to 5 units to control which all possess a skillshot, wow skillz MLG420blazeit. But the thing is landing a single skill like mirana's arrow is harder than landing 90% of the lol skillshots. Landing Lina's or Leshrac's stun without a setup requires more skill that pretty much anything in lol from back when I played. They might have added a harder skillshot since then. Not counting crossmap Ashe arrow since those are entirely reliant on your opponent not moving from where you assume he'll be(that is unless you're sniping a guy running away so you can actually plot his course and aim there, I mean like shooting from bot to top for your jungler gank). Ezreal ulti maybe, slow cast time and global range so pretty good. But don't act like every lol champion is really skill based and shit, because a lot are simply not. They require skill in terms of positionning, timing abilities right, choosing the right targets and such, but not because their skills are skillshot. Annie spells are skillshots but don't require any fucking skill to land.
Anyway sorry for the shit derail, I'll just put him back on ignore, I was wondering what he posted here since he came back in the dota thread to have the last word and mock a new player asking for help in the process. Look forward to the LoL mod in dota2 engine once Valve releases the tools though. Garen vs Juggernaut.