It's difficult for us to anticipate what will work for you. I can only relate to my own experience but here's a few observations. First, size of the grip in relation to your hand is important.
Your 4" length is a good choice. Watch that it doesn't get too long and the glass to glass measurement accounts for the angle of the glass. If the glass is .040 and is over a 040 lam, at a 45 deg angle that adds .160 of length at each end and thus lengthening the grip area by .320. It's not a bad thing functionally but it doesn't have that "hill" look.
On the depth, it's just my opinion that it's better to end up a little smaller than larger. This one below was 2.25 before the leather wrap. It was difficult to grip but the addition of the leather wrap with the flesh side out made it a comfortable shooter. Still if it was even 1.75" deep with the wrap it would still be a good fit for me.
The other consideration on depth is torque. The deeper the grip, the longer the lever and the easier to torque the grip.
I suggest starting with a "racetrack" flat profile and shoot it for a while before making any changes. You can always take more off and it's easier than rebuilding with Bondo.