You can use this tool
https://bitcoinops.org/en/tools/calc-size/ to discover transaction size of Native SegWit (P2WPKH) and Taproot (P2TR). Personally i consider Taproot as good choice due to smaller input size, which lead to lower fee when you spend those Taproot UTXO. But since you mention PayJoin/CoinJoin, you probably want to use whatever address type used by other participant to make tracking more difficulty.
Thank you for the tool suggestion. Yeah I can see indeed Taproot is even better.
I understand also your point about PayJoin/CoinJoin requiring similar address types, you're trying to tell that while P2TR is more efficient, since other participants don't use it as much for the time being it may not be the optimal choice.
As I was browsing around, I found this
https://en.bitcoin.it/wiki/Bech32_adoption . In the past I noticed how somehow Electrum was able to construct UTXOs that were slightly cheaper than what Sparrow Wallet builds, but I will give Sparrow wallet again a try since they seem to have support for Taproot Multisig.
Thanks a lot.