now, increasing the max pdch will not change ANYTHING if your cell is highly loaded in TCH.
could you check these indicators:
nb of PDCH per TBF (this is a new report, located in MONO Object Distribution > GPRS distribution)
ratio of usage of each MCS.
the opint is: why do you have such low throughput: because users have low number of PDCH, or because the MCS is low ?
if low PDCH –> you must increase the max pdch high load, and try to decrease the CS load
if low MCS –> increase the max_mcs (i forgot the exact name), check your Abis & Ater are not congested, check there are no interference in the cell.
to summary: check all your GPRS indicators in order to diagnose the problem 🙂 you are already trying to fix the parameters, but you didn’t finish the investigation. It’s like you’re filling up a car’s fuel tank when a tire is flat.