That would be justice because the Brewers' move to the NL was what prompted the imbalance that made the Astros' switch "necessary". Simply move them back.
But Selig (Milwaukee's former owner and still benefactor) claims doing so would harm the Brewers' "great rivalries" against the Cubs and... well, the Cubs.
There were 25+ years where the Brewers competed with the White Sox and Twins but *those* rivalries apparently didn't count.
Umm, 100% wrong. The imbalance was caused by MLB expansion from 28 to 30 teams in 1998. Neither league wanted to add 2 expansion teams and with interleague play in its infancy, having two 15 team leagues was a logistical nightmare. The MLB owners voted to move an existing AL team to the NL. The Kansas City Royals were given the first option to move, but their owner decined. The Brewers were given the second option. Acting Commissioner Selig, fearing that the votes to approve expansion might vanish if he declined to move, agreed to take the Brewers to the NL.
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But Selig (Milwaukee's former owner and still benefactor) claims doing so would harm the Brewers' "great rivalries" against the Cubs and... well, the Cubs.
Actually, you fail to recognize that Milwaukee & Chicago (and Wisconsin & Illinois) are intense longtime rivals in all facets of life. Wisconsinites call our immediate negihbors to the south FIB's - which stands for effin Illinois bastards. They dubbed us Cheeseheads. We turned that "insult" into a clever franchise of novelty headwear. They haven't come up with a way to market FIB's yet, although they did export one to Washington, DC.
Beyond that, the cities of the NL Central - Milwaukee, Chicago, Cincinatti, St. Louis & Pittsburgh are very similar. All were historically settled by German, Polish and Italian immigrants with an industrial (and now Rust Belt) base. On the field, the Brewers have developed intense rivalries with the Cubs, Cards & Pirates - slightly less with the Reds. You are also forgetting that the Milwaukee Braves were intense rivals with the Cards & Cubs.
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There were 25+ years where the Brewers competed with the White Sox and Twins but *those* rivalries apparently didn't count.
Ah, now your baseball ignorance is really showing. Despite their geographic proximity, the Twins and White Sox never developed a rivalry with Milwaukee. The Brewers were only in the same division as the Twins & White Sox for 6 years (AL West in 1970-71, AL Central (1994-97). If you consider the old unbalanced schedule, the Twins & White Sox were as much rivals of the Brewers as the Angels & A's.
Ironically, the Brewers & Twins developed a rivalry only AFTER the Brewers moved to the NL and were desginated as the Twins' interleague rival.
You could call the Indians a rival of the Brewers since they played together in the same division for 25 of the Brewers 27 years in the AL. Or even the Tigers (21 of 27 years). But the Brewers, Tigers & Indians were never very good baseball teams at the same time, so they never developed on-field rivalries. Truth be told, the Brewers' biggest on-field division rivals in the 70's & 80's were the Yankees, Red Sox & Orioles or even the Blue Jays.
The Astros really only lost one rival in their move to the AL West - the Cincinatti Reds. The Astros and Reds played in the same division for 43 years. But other than the Reds, the Dodgers, Giants & Padres were all bigger rivals for the Astros than any NL Central team.
Would it have been better to move the Diamondbacks or Rockies to the AL West? Perhaps. Even so, the Astros were definitely headed to a West division.
It's unfortunate that the novelty of interleague has worn out and the big market owners wanted to balance schedules, divisions and playoff opportunities at the same time as the Astros required their votes to approve an ownership change.
Look at it this way, at least you get to maintain the natural Dallas/Houston rivalry and play more games with the Rangers.