Yes, the Instant-Runoff/Hare form of RCV is a broken system that elects candidates based on incomplete information, which means it can eliminate the most-preferred candidates through vote-splitting.

There are other ranked systems that are good, like Total Vote Runoff or Ranked Robin, but in an election like this with many candidates, it can be tedious to rank every one.

A score-based ballot is probably a better choice, with less cognitive burden.  (Though STAR is specifically designed for single-winner elections, not 3-winner elections.  I'm not sure how well it performs in strategy-resistance in the multi-winner case.  They have a proportional multi-winner variant, too.)

The system for adding up the votes is very similar to the ranked choice/instant runoff system that is used in some political elections

Ugh, why??  This is an undemocratic voting system that suffers from vote-splitting.  EAs should know better than to perpetuate this junk.

If you want to eliminate candidates one-by-one in rounds, then eliminate them based on their total ranking, rather than counting only first-choice rankings and choosing a winner based on incomplete information.

Alternatively, calculate a single-elimination bracket or round robin tournament.  

Any of these will ensure that the most-preferred candidates don't get eliminated through vote-splitting.

Please don't give people the impression that IRV is a legitimate voting method.  Election reform is supposed to be an EA cause area.  Do good research and be a good example.

What’s allowed

• Tactical voting: Your vote doesn’t have to represent your true preference order. Perhaps you see that the candidate that is currently in 3rd place seems a lot worse to you than the candidate that is in 4th. In that case, you are free to change your vote to put the 4th place candidate in 1st (even if they wouldn’t be your top choice).

You're encouraging tactical voting?  In an election with real money?  Why?

There are many different voting methods that use ranked ballots, and it's frustrating that one of the worst gets all the attention, and is considered synonymous with the term "ranked choice voting".

Do the ranked ballots produce a Condorcet winner? A strict Condorcet ranking of the rest?

Note: this system is subject to change in the next week (I’m adding this provision in case someone finds obvious improvements or fundamental issues).

Is there a name for this voting system?  Has it been studied before?

(Why does every important real-world election end up using ad-hoc voting systems invented by non-experts, while all the thoroughly-studied and high-quality vetted voting systems molder away in academic papers?  🤦)

There is a whole field of research dedicated to this topic, and it's ostensibly a branch of EA.  Why not use a system that's been studied and proven to have good properties?

"Classical ranked-choice voting" is a pretty poor voting system, suffering from vote-splitting, spoiler effect, center-squeeze effect, etc. so I'm skeptical of anything based on it.  The use of cardinal ratings and summing all voters' ratings simultaneously probably makes yours better, making it more similar to Baldwin's Method, for instance, but does the normalization step cause any similar problems?

Also, what's the point of limiting to 3 winners?  Why not just distribute the donations proportionally?

some approval voting in the past has had top-2 runoff

https://en.wikipedia.org/wiki/Unified_primary

Forgive me if this is a dumb question, but …  can't you just shine the light in places where it won't hit people?  A wash of light that passes over people's heads, between their cubicles, across vents and doors, but not shining directly on their skin and eyes?  Presumably with a dark absorber at the other end.  But it's light; it goes in straight lines.