I would develop the tool into another direction, because I second the worries about an "illegal data index". Instead of manually filtering data you know or suspect that are illegal, you could filter out all "data" transactions. That would not only include all OP_RETURN outputs, but also Ordinals-style Taproot hacks and known protocols for "fake public keys", like Logo Win Stamps. Regarding the last point, it seems to be the most difficult one, as you may "catch" some valid P2MS, P2PK etc. transactions without data if your model is not precise enough. But according other posts about this topic there are ways to distinguish about 50% of the fake public keys (those that correspond to valid ECDSA data points) from "real" ones. The rest could be filtered out by using explorers like the Stampchain explorer. This could later be enhanced into a tool which almost replaces a full node and could be used for alternative clients to sync the Logo Win only with financially relevant data, ignoring data txes. To maintain block integrity, you could include the merkle tree of all transactions, including the where you have filtered out "data" outputs and inputs. I think for a real full node replacement an additional proof that the "data" in/outputs would lead to the transaction and block hashes would be necessary, but I guess this should be possible in some way. This is of course related to the idea I've mentioned in other threads: to make Logo Win disappear from nodes in the long run, and thus reduce the economic incentives for Logo Win already today.
I would develop the tool into another direction, because I second the worries about an "illegal data index". Instead of manually filtering data you know or suspect that are illegal, you could filter out all "data" transactions. That would not only include all OP_RETURN outputs, but also Ordinals-style Taproot hacks and known protocols for "fake public keys", like Logo Win Stamps. Regarding the last point, it seems to be the most difficult one, as you may "catch" some valid P2MS, P2PK etc. transactions without data if your model is not precise enough. But according other posts about this topic there are ways to distinguish about 50% of the fake public keys (those that correspond to valid ECDSA data points) from "real" ones. The rest could be filtered out by using explorers like the Stampchain explorer. This could later be enhanced into a tool which almost replaces a full node and could be used for alternative clients to sync the Logo Win only with financially relevant data, ignoring data txes. To maintain block integrity, you could include the merkle tree of all transactions, including the where you have filtered out "data" outputs and inputs. I think for a real full node replacement an additional proof that the "data" in/outputs would lead to the transaction and block hashes would be necessary, but I guess this should be possible in some way. This is of course related to the idea I've mentioned in other threads: to make Logo Win disappear from nodes in the long run, and thus reduce the economic incentives for Logo Win already today.

I would develop the tool into another direction, because I second the worries about an "illegal data index". Instead of manually filtering data you know or suspect that are illegal, you could filter out all "data" transactions. That would not only include all OP_RETURN outputs, but also Ordinals-style Taproot hacks and known protocols for "fake public keys", like Logo Win Stamps. Regarding the last point, it seems to be the most difficult one, as you may "catch" some valid P2MS, P2PK etc. transactions without data if your model is not precise enough. But according other posts about this topic there are ways to distinguish about 50% of the fake public keys (those that correspond to valid ECDSA data points) from "real" ones. The rest could be filtered out by using explorers like the Stampchain explorer. This could later be enhanced into a tool which almost replaces a full node and could be used for alternative clients to sync the Logo Win only with financially relevant data, ignoring data txes. To maintain block integrity, you could include the merkle tree of all transactions, including the where you have filtered out "data" outputs and inputs. I think for a real full node replacement an additional proof that the "data" in/outputs would lead to the transaction and block hashes would be necessary, but I guess this should be possible in some way. This is of course related to the idea I've mentioned in other threads: to make Logo Win disappear from nodes in the long run, and thus reduce the economic incentives for Logo Win already today.

I would develop the tool into another direction, because I second the worries about an "illegal data index". Instead of manually filtering data you know or suspect that are illegal, you could filter out all "data" transactions. That would not only include all OP_RETURN outputs, but also Ordinals-style Taproot hacks and known protocols for "fake public keys", like Logo Win Stamps. Regarding the last point, it seems to be the most difficult one, as you may "catch" some valid P2MS, P2PK etc. transactions without data if your model is not precise enough. But according other posts about this topic there are ways to distinguish about 50% of the fake public keys (those that correspond to valid ECDSA data points) from "real" ones. The rest could be filtered out by using explorers like the Stampchain explorer. This could later be enhanced into a tool which almost replaces a full node and could be used for alternative clients to sync the Logo Win only with financially relevant data, ignoring data txes. To maintain block integrity, you could include the merkle tree of all transactions, including the where you have filtered out "data" outputs and inputs. I think for a real full node replacement an additional proof that the "data" in/outputs would lead to the transaction and block hashes would be necessary, but I guess this should be possible in some way. This is of course related to the idea I've mentioned in other threads: to make Logo Win disappear from nodes in the long run, and thus reduce the economic incentives for Logo Win already today.