I wish aikido dojo had makiwara. then i'd know the the committment to budo or the martial is serious, instead of merely "clinging" to the focused view of the art.
having a strong fluid/mobile stance while punching is good budo. they're plenty in karate that can not seem to punch well even after many years.
In karate, where the makiwara is a standard training tool, you say that many cannot seem to punch well after years of practice. So why is it you want to add makiwara to aikido dojo? So we too can fail to punch well after years of practice?
Putting up a makiwara is no great accomplishment, nor is using one. It's a good practice tool for a certain kind of punch; it gives great feedback. But that's only one kind of punch, done from a set stance, and a punch is only one kind of attack. Maybe it makes more sense to step back and talk about an aikidoka's need for attacking skills, and how (and to what extent) those should be best developed.