Casey, founder of Ordinals, said in a post on the X platform that runes and inscriptions will be as programmable as Bitcoin, which means that improvements to Bitcoin's expressiveness will also affect the expressiveness of runes and inscriptions.
For example: OP_CHECKTEMPLATEVERIFY will allow public minting to be organized as OP_CTV trees, which will expand into UTXO subpages containing runes. This will allow users to obtain runes or transactions without being mined and without paying any fees, which requires users to bid to participate in public minting and pay fees to obtain runes.
SIGHASH_GROUP can use signatures more flexibly to commit to a set of inputs and outputs. It will allow a variable number of runes to be sold from a single UTXO without splitting, because users can commit to input UTXO, output runes, and payment outputs. This also makes it easier to promote runes to the Lightning Network for some mysterious technical reasons.
The standardization of the Taproot signature appendix, which carves out unstructured data, will allow inscriptions to be made in one transaction, rather than requiring a commitment transaction and a reveal transaction. There are more new features to look forward to in the future.