I was wondering about the mechanical and RP effects of these spells.

On the mechanics changes, the durations for the spells Dominate Monster and Mind Blank are altered. Do these same alterations apply to the above mentioned (similar) spells? If not, could you please explain why?

Secondly, I know that how you RP being affected by such spells is not strictly enforced, but could the DM team make a recommendation or give some guidelines?

Eg. you should not lie if dominated. No one can read your emotions at all if mind blanked, etc.

Any input regarding this?

Lesser Mind Blank retains its default duration (turn/level). I admit not having tested the others, but suspect it's the same. The RP policy surrounding spells such as Dominate Person may change soon.