Sion could use a buff.
At the moment I believe that Sion is fairly weak as a champion, because of how most of his kit requires a more skill to pull of than it gives benefit.
Take for example his ult, it can either set up a good fight, which most other champions that fall under the category of tank can do, but it can also be dodged rather easily, thus putting Sion out of position. Another thing to note is that to use it to good effect, you need to be far away from the fight, meaning that your ult will more or less be something that hits after the fights started, which is not a good place to be as a character. Another issue would be his q, it suffers from the same very hard to use, and lackluster gains that his ult does, and it requires the player to both be in a place that he can reliably hit opponents with the cc portion, as well as being able to not get cced by anything in the process, Because of this simple problem that Sion faces, I think that there must be a problem with this. An issue that I see often enough is that a Sion will charge into a team, and attempt to charge his q, only to be stopped and be forced to begin the channel again, which in turn means that Sion did not have real importance to that fight, except for taking maybe one hard cc.
A way that I think could fix this problem of Sion not actually being a major issue for teams to deal around is for Sion to be given a cc proof when he is channeling his q. I know that this sounds like it would be very strong, but in reality it would not be that big of a buff, it would just mean that Sion would have a better opportunity to actually affect a fight more than just taking one cc spell, and actually being able to threaten a piece of ground. Some people would probably want to know where the counter play against this is, and the answer to that is simple, The counter play against Sions q actually comes with the ability itself, it has a fairly long channel, and its thin enough to where if you walk to the side you should make it out before he gets access to his stun/knock-up. If this did show to be too strong, because people would be able to just spam it for a second a cc proof if the needed it perhaps, damage could be moved from his e into his q. The damage could also be shifted from the beginning of the spell to the end, to reward players for hitting this very easy to miss ability.
I believe that this change will both increase the skill ceiling that Sion has, as well as decreasing the skill floor, and overall it would increase the viability of Sion, as well as the pool of viable champions as a whole. Thank you for reading my post.