Best Resources/Guide for Quant Interviews?

Could we start a list of resources for preparing for Quant Interviews? Have a little extra free time due to Corona now and wanted to get a head start for the Fall.

I'm going to go through Heard on the Street and a Practical Guide to Quant Finance Interviews and was wondering if other people know of other resources. Also planning to grind the mental math sites too but closer to my interviews as I found the speed typically falls off if I don't keep doing it consistently, while it only takes a week-ish for me to ramp up. For algorithms, I'm just planning on doing Leetcode (I can be hit/miss for FAANG-level companies now, but I know quant companies ask harder questions on average).

Specifically, I know I need help on brain teasers, market-making games, any extraneous math concepts they might ask, any probability that might not be in the two books I mentioned, and I guess any other topics that I might not have already mentioned. Any additional practice problems would also be greatly appreciated!

As a side note, I was wondering what other things I might be able to do to improve my profile other than just doing interview prep. Unfortunately, I failed my interviews for quant finance this past year, so I'll be doing another SWE Internship. I'm a Junior CS major at a school typically considered top 20/30, but not a target for finance (none of the firms I'm interested in recruit here, but being on the west coast might have a little to do with it). My GPA isn't too great (3.3 but I expect it to be around 3.4, hopefully 3.5, at the end of this semester). I've interned at 3 well known tech companies now (including Google, but the other 2 are well known although not traditionally as highly regarded) and will be interning at a Unicorn this upcoming summer. As a result, I usually get pigeonholed into SWE and am trying to figure out how to not do that. I've gotten to the onsite at DRW, HRT, Bridgewater, and PDT before (and actually thought I did really well at PDT and pretty well at Bridgewater) but didn't make the cut. I've gotten online challenges/first round interviews from Akuna, Belvedere, Optiver, Two Sigma, and a few more I can't remember off the top of my head as well. I haven't ever heard anything from Jane Street 5 Rings, Old Mission, or Tower. I was talking to Citadel earlier in the year and they said they would re-open conversation with me later in the fall this year.

Knowing this, what should I focus on to optimize my chances?