One important thing to keep in mind is that ML teams are very rich but not all spend their money in the same way.
I always felt the system was designed for most players to fail in staying in the game because of the pay. A lot of players drop out because they just cant afford to stay in. The career guys keep playing but not always here in the US. They get paid a lot of money in a short period of time so that supplements their seasonal pay.
One thing to keep in mind, a milb roster may be at 25, but sometimes they keep guys on the DL for reasons other than they are injured. In other words, I think that you will see less opportunities if the pay increases.
For most, I don't feel more money will keep them in longer, because teams will release players sooner because they are not going to pay someone more if they don't see a future for them or they are now paying for one what they used to pay for 2.
As I always have told my kids, to be careful what they wish for.