I think ideally the players are staking SPS for player staking, tournaments, governance and other reasons to stake as opposed to purely yield.
Players are inherently able to move faster than a DAO in their positioning for yield, so I would argue that the DAO has a fiduciary responsibility to do relatively safe investments or only those investments that will specifically benefit the ecosystem (preferably both).
The DAO should be excluded from proposal voting - it already has 2 mil staked SPS that doesn't seem to be screwing anything up. But worst case, the DAO staking more SPS requires more engagement and voting for a proposal to carry. I see that as a positive and not a negative.
RE: SPS Proposal - SPS.DAO should stake an additional 28,000,000 SPS for a total of 30,000,000 SPS