There are fewer problems with pick, ban, or dodge champions but there are bigger balancing issues between classes.
There were periods in previous seasons where if they enemy team had a kassadin or a lee sin or a graves or a fizz then the game was pretty much over at the start. Now, there are actually very few champions that are such outliers I feel I need to ban them to have a good chance of winning (tank ekko being one of them). In that sense I think this season is fairly balanced.
However some classes are too strong (marksmen), some are too weak (mages, which might be fixed with the update, who honestly knows?), and some items synergize way too strongly with champions they shouldn't be so good on (iceborne gauntlet on ez) and not well enough on who they should synergize with (tank items on true tanks, like sejuani). I think tanks are generally weak but are seeing play because of adc power (e.g., malphite's armor passive and attack speed debuff make him strong against all ad teams even if tank itemization is weaker than it has ever been. Specifically, pure tank items are weak right now -- we've had thornmail nerfs, frozen heart nerfs, randuins nerfs, and the stronger tanky items are more bruiser oriented, like deadman's plate and sunfire).
In this sense the season is imbalanced.
I'm not too worried about the class imbalance because it is sort of inevitable when riot overhauls one class at a time, and I think they need to overhaul the classes to make lol a better game. The class imbalances don't make for stupidly unfair lanes, but instead they make fore a very dominant meta. The class imbalances will shift with new class updates, the meta will shift, and this will keep the game from getting stale. I don't like the class imbalances, but class imbalances are better than profound champion imbalances.
I'm less worried about class imbalance than I am about snowball mechanics this season. Towers are weak, the masteries add a ton of damage, and the death timers are long. So most games end in a stomp one way or another. It's not fun stomping and it's not fun being stomped. I miss the tension that was present in previous seasons. It's no fun seeing a lane 2/0 at 8 minutes and realizing that the game is pretty much over.