Thanks for making this proposal on risk parameters!
I think 1inch Protocol and token generally have healthy fundamentals, as well as good liquidity and trading volume metrics. But I have a concern about the concentration of tokens and potential for malicious distribution.
Currently around 88% of token supply is held in the 1inch foundation multisig, requiring 2/3 signers. This amounts to around $7 billion. If this was compromised, an attacker would be able to borrow up to ~$4.5 billion in assets from the protocol, and the debt would likely result in a near total loss to Aave.
I’d feel more secure accepting 1INCH token as collateral if the treasury was transitioned to a more reliable mechanism - potentially more signers on the multisig would help, or transferring the bulk of tokens to a multi-day timelock mechanism to give advance notice of distributions. In the long run transitioning to full token holder control of treasury assets is likely the most secure option.