The Parity, Even and Odd.

I just heard that MLB's Huston Astros is going to transfer from NL Central to AL West in 2013 season.  Now five ball clubs will be belonged in each division in each league.
That seems fair. I always felt strange that there were only 4 teams in AL West.
But I couldn't expect this to happen at all for one reason, the parity.

There are 30 MLB teams, currently 16 in NL and 14 in AL.
Because both leagues have even number of clubs, they can play against each other everyday.
But from 2013,  there will be 15 NL teams and 15 AL teams.
Then, one team in each league have no opponents in its own league.
So I couldn't see this become a reality.

It seems that an interleague game will be played somewhere everyday.
The next season's schudule intrigues me!

First of all, I expect that the "interleague period" in May and June will be discontinued.
There are 15 teams in AL x 5 teams in one division of NL x 6 games/series = 450 interleague games.
There are about 162 days in the regular season.
So roughly 450/162 = 3 interleague games will be required each day.
If there are 3 interleague games each day, the remaining 24, 12 in each league, can face each other.