Valer
First Class Debutant
As I mentioned before the step up in terms of glovework is less than the step up of batsmanship, due to the more standardised nature of the keepers role as evidenced in practice (see 1st class to test keeping, even (1sts) grade to 1st class.)But playing against Mars with their genius batsmen could mean that chances are extremely rare, therefore you can't risk letting them go down due to less able keeping.
Furthermore expecting chances to be "rarer" implies that exceptional batsman are further from the norm than exceptional bowlers -- that is on similar pitches bat will dominate ball significantly more as the standard increases...