I doubt Mahindra offers another tranny option for the tractor, as they have other tractors in the HP range that are available with more gears.
For our purpose the 8X2 tranny works well for haying. If we were baling 10,000+ bales a year it wouldn't be ideal, but we don't bale that many bales. The Ford 4000 we have used for years has had no problems, and it has a similar 8X2 tranny. The 6025 specs a lot like the Ford 4000.
These 25 series tractors are aimed at the same market as the JD 5X03 series, people who want a simple tractor at a bargain price. Mahindra does not market the tractor specificall for haying, but markets them more as a general purpose tractor.
The reason I mentioned the haying is because a tractor like that would be ideally suited for that purpose for me.