I'm a fan of enchantmint, i have two L10s and an L1.
Great with witch hazel but EAvil devs nerfed it so it won't kill cardio or z mech anymore.
I don't know your current mint levels but keeping it at L4 and conserving your stash is a good plan.
It costs 4,150 mints to buy and max out just one powermint and there simply aren't enough mints given out in the new seasons streaks for new players.
Try to level them up to L2, L4, L7 or max (ho ho ho) as those are the levels that knock time off the refresh rate.
The big four are spearmint, reinforcemint, bombardmint, and concealmint, appeasemint and enchantmint are ok, the rest are a bit meh.
The levelling up process is the same for them all (except enchantmint) so check them out on the fandom site.
You might prefer a particular powermint depending on your style of play so bear that in mind, we are about due an improvemint event where all currently released powermints and their seeds are in the store at the same time but it's entirely down to EA when or if it happens.