Love the drawings haha.
I believe the 1st one is more stable as CH3 is a slight donating group. A slight donating group would make the negative charge on the oxygen slightly less stable, so having less donating groups makes it more stable...at least in my mind.
A more stable base = a stronger acid = a weaker base. This would make the 2nd one a slightly stronger base. Hope that I am right, take this with a huge lump of salt as I am going off the top of my head and did not look it up.