First, consider, is there any affinity between Etherchannel port usage and switch member ports? If not, what do you hope to achieve?
Second, don't know if Cisco still has this recommendation, but way back for 3750 stacks, they recommended uplinks not be placed on a master switch. This to avoid any additional loading on the master.
Personally, I've dealt with edge stacks, up to max number, where we usually only had a pair of uplinks, on different switch members, just for redundancy. If up link bandwidth was a concern, we usually used higher bandwidth uplink ports rather than increase number of uplinks. Two major reasons for that, first if you're using optics, lots of transceivers can become more expensive than higher bandwidth ports. Second, as Etherchannel and/or most L3 ECMP don't dynamically LB, higher bandwidth ports perform better.
If you're really worried about performance, especially on a stack with many members, either use multiple smaller member stacks, or use a chassis, the latter often price competitive for a max member stack vs. large number of slots chassis.
