I would just let the SRS do the work for you here. If you do the reviews each day, the kanji that don't stick as well will become obvious and you can rework your stories then.

That being said, I didn't use this site for rtk (used anki) so I'm not sure if it's actually possible to review early.

Thanks for replies. I did the "delete all cards" trick and had a very lengthy review, but in the end, I didn't notice any difference, I had all the cards memorized very thoroughly.

So, let me abuse this topic of mine and ask out-of-the-way question. I hear a lot and read a lot that people have an SRS deck for RtK as well. Do you recommend using koohii along with SRS or should I just stick with koohii only and then use SRS for later study? (vocab and sentences, I assume?)

When I first started RTK 1, I used surusu (AJATT's SRS platform). It's not exactly bad, but it's extremely bare-bones (at least, it was when I used it). There were a couple of features in Anki that really impressed me (automatic yomi generation, public decks), so I decided to start using Anki instead of surusu. When I made the transition I had to migrate ~1800 kanji + stories manually into an anki deck. And that was a bitch.

The moral of the story is: Try to find the SRS platform you're likely to be most comfortable using, as early as possible in your Japanese quest.

I've never used the RTK review function myself (I've only used this site for the forums and to see other people's kanji stories), but from what I understand it doesn't support adding your own kanji. If that really is the case, I'd recommend migrating since you're bound to come across a kanji not included in RTK 1+3 sooner or later.