I Use a Gamepad, MNK was my Main before NIN, i have about 4 empty slots on 2 page setup using the Right Bumper (or R1 for PS Controllers)
Using macros just slows your DPS you cannot que abilities, you cannot logically decide when and where to use Buffs. etc its just not a good idea.
If you really are running out of space on your gamepad to effectively use your MNK you need to rethink your priorities on abilities you're equipping to it
also i didnt see anyone mention this but as a gamepad user i tend to make my "spammy" stuff on my first page, your main combo abilities and stuff like that, and leave all the not so often used stuff, like Second Wind, Mantra etc on the second page...
TL;DR Don't use Combo macros on MNK, it's just a bad idea if you're trying to actually perform well at the job.