Sure, have you read Governance - proposal for technical realisation for voting - #23 by scholtz ?
There is no real means of searching the blockchain, and only thing how it can be solved is the custom asset or have the amount indexed properly… I do not consider the search by note prefix as effecient enough because it never can be indexed properly by the current databases, but to index by the amount it is very possible, but it needs to be indexed…
Index by the tx amount can be usefull for a lot of usecases… this is just one of them…