Should enterprise and SMB sellers be on the same pay mix?

We are a 900-person software and services company in Bengaluru selling into India and the Gulf. Until now every seller has been on 60/40 base to variable. We are splitting the team: 25 enterprise account executives with deals that take nine months and average around 40 million rupees, and 60 SMB sellers closing several small deals a month.

The enterprise leaders want 70/30 because their sellers can go two quarters without a close. The SMB leader wants 50/50 to drive volume. HR is worried about two classes of seller with different total pay.

Is a different mix by segment normal practice, and how did you handle people who move between the two?