Ripoff the Intel Tick-Tock strategy, but for patches.

That is to say, Even numbered patches introduce new content (even if its just the fortnightly cosmetic promo item). Odd numbered patches service older content.

Sure, occasionally patches do tweak long time 'stuff', but it might be useful in the long term to modernize older 'stuff' on a regular schedule in order to fit in alongside the new 'stuff'. I guess this depends on if you believe some older 'stuff' has issues or if everything is fine the way it is.

tl;dr
tweak more often