Acctually, it could be applied for any Slavic language with not to much effort, but it would take enormous costs for switching with no real gain.

Exactly. No real gain. Stalinava Nadzieja, you have easy talking. You won't have to learn it ever. But if our beloved Croatians would do such a move, we, as their neigbours and themselves are pretty screved with learning it. ;D In the end we could also switch back to bohoričica as it is truly and uniquely Slovene. But that wouldn't be that much of a problem.