I'm very bad at cases and I am graduating in December. Is there a way to improve, or should I stop applying to MC positions and focus on something else?

Hi everyone. I recruited for consulting internships for Summer 2021 and eventually landed at an EC shop. I didn't get a return offer. I did terribly in all of my MC interviews for Summer 2021. 

Now I am recruiting for FT positions in EC and MC while graduating in December. I practiced some MC cases over the summer, but not much. I mostly practiced with people who were iffy with cases as well, unfortunately.

 I think I have gotten a bit better at cases in terms of knowing how to create more flexible frameworks and being able to do math more quickly and accurately. I am also much better at market sizing and being able to think on my feet (but I am still not a fast enough thinker). 

My problems are:

1) I take too long to structure the problem or have too many buckets. Sometimes the frameworks are not really appropriate or not MECE. 

2) I do the math slowly and sometimes miss zeroes. Sometimes I can't figure out what math to do.

3) I sometimes "freak out" if I have to do math in front of an interviewer (not confident in my responses). 

4) The delivery of my answers is poor because I do not sound confident at times. 

5) I'm not very creative with brainstorming. 

6) It can be hard for me to think on the spot.

7) Business intuition sometimes doesn't feel natural to me.

Do I just need more practice, or does this warrant serious coaching / giving up on this career path?

So far, I've done 3 case interviews this recruiting season and have more lined up.

I got rejected from LEK because the interviewer had to redirect me to the client goal and because I had to be babied too much during the quant strategy case in terms of math and problem-solving.

I also interviewed with an MBB yesterday and I'm pretty sure I did not do well during the second case because I took too long on the math and made assumptions without looking at all of the data. I also had an extra zero in my math. 

I haven't heard back from the 3rd case interview, although they said they'd get back to me Monday or Tuesday (of this week) with a result, so maybe I was rejected.

If anyone has advice, I'd appreciate it. I talked to someone online yesterday about my situation and they said that "the only way to fix my problem is to go back to my sophomore year and drill cases," so I understand I may be SOL.