You are 100% correct. These threads are meant for helping one another and improvement so I’ll break down Blanka’s side of things below. (keep in mind that I’m terrible with terms and techno babble. I just know what works for me)
Unless you have reason to go for a better option, start the round with a jump back LK, it means that blanka has no attacking option to get close to you, it hits his vertical roll on the way up, everything else he does misses, and if he does a fast horizontal roll he’ll cross under you, you’ll hit him out of it on the ground and can block string or combo into a st.lk, st.lk, st.lk chain and throw him or tag on a standing HK or MK if you’re confident with that chain.
OK, this is a good tactic to start things off but here’s what I do to counter that…
Fast horz ball and mash electric so that Bison lands on it OR if I’m quick enough, I’ll hold back and press FP for a bite.
Standing jab stuffs all of blanka’s vertical balls clean. Blanka’s main aim in this match is to get in on bison and start his jumping short bullshit.He can tick throw really well, and he has a devastating low forward, low forward xx vertical ball combo he can hit confirm into if he gets a low hit. Stopping him from knocking you down is absolutely crucial, because his corner mixups are scary. Look to slide out from under repeated jump in LKs, or jump back LK to anti air him. Bisons diagonal Jumping LK will beat most things in the air if you’re higher than the opponent. Because of it’s hitboxes, and it’s priority you’re fairly safe if you’ve jumped before the opponent or are higher in your jump arc, and regardless it will beat a lot of things clean even if you’re not. It’s one of his better normals and is under utilised IMO.
Again good stuff but Blanka’s game is about closing the gap and if he does. Your options are severely limited. Here’s a freebie… if Blanka is biting Bison and Bison is in the corner. The natural thing for most Bisons to do is to jump up with a kick or MP. Blanka’s counter is to also jump up and smack ANYTHING Bison throws ot with FP. It’s so nice. 
You can bait his vertical ball and hit him out of it with diagonal jumping forward from the front, your timing has to be good though, don’t try meaty jumps or safe jumps on him, his up ball is active on the 1st frame, he’ll win every time. If you want to bait his up ball, jump later than you normally would, so you’re in mid air above him when he’s waking up. Crossing him up is very risky, i would steer clear of it, because a knockdown from an up ball at that range could be very costly.
The arc of the rainbow roll counters the diagonal jump counter. Also works wonders vs Vega dives. Expert Vegas know how to stuff vertical balls but they get smacked out o the air by the rainbow roll because of the arc.
Once you can keep him at a distance when you want to, and make him afraid to roll at you he’s completely harmless. If you’re full screen away, a great trick is to spam standing jabs, and particularly standing medium kicks, because those will beat all of his vertical balls, and will mean that he can’t go for a short roll or a short roll into bite, or a hop, to close distance. The only way he’ll be able to get closer and keep charge is to jump. When you see him advancing get ready to use J.LK and particularly J.MP Juggles to catch him out of the air, and try to throw out meaty low forwards, standing forwards or standing roundhouses for him to land on afterwards.
S. jab far away is good but you better be crouching when you do that. I sometimes advance with j. roll into slide for a fake and knockdown. Then the fun begins. 
Or I’ll use the opportunity to build up my super. Which makes it worse for the Bison player. Now you REALLY get no free jump-ins.
When you get him knocked down, close standing LK tick throws are REALLY effective against him (thanks to maverick and Jigglynorris for that tip). Keep mixing up how many LKs you do before the tick, and he can really only try to guess when to counter grab you.
Standing LK is good but again can be countered with Blanka’s bite counter. For the S. LK to be efective, you must do them in tight sequence and minimize any gaps in between LKs. That being said, the mistake most Blanka players make when trying to counter with a bite is to hold forward and FP. That is not good. I always hold back and FP. I get better than 50/50 results with this counter.
If he does get a bite on you, you want to try to mash out of it for a bit, but be ready to use jumping MP juggle instantly as soon as you’re free. Blanka will bite you then jump in with jumping short to reset his tick throw trap, you HAVE to be able to escape this. My default action here is mash/wiggle for 1-2 seconds, forget about keeping charge, and then just hold either up+back or up+forward depending on my position and get ready to hit J.MP as soon as i can after landing from the bite. You have to be quick, but there is a small gap that you can use to escape after his bite ends.
This strat is good but Blanka’s counter to your escape suggestion is for Blanka to forward hop after the bite and then vertical ball. He gets right under you and knocks you out of the air. I almost never go for j. short after a bite.
**Use lots of pokes, especially low forward to build super meter, and keep your super in case you get cornered, don’t throw it out randomly or you’ll waste it, and if blanka throws out his super randomly (which he shouldn’t), DON’T JUMP. Take the block damage if you can, devil’s reverse if you need to do something to get out of the way, or as a last ditch effort, wait for a second or 2 so he has to roll, and then jump forward over him and hope he doesn’t hit you.
There is no jumping away from Blanka’s super. You MUST take the block damage or hope to poke him out of it. If you wait and anticipate your jump even perfectly to escape the super, Blanka can still counter with a RH vertical ball to still get the knockdown. I do this ALL THE TIME. This strat works great vs Sim players as well.
OK, that’s my 2 cents. Now you gotta find counters to my counters.