I don’t mind any sufficiently competent* person having unchecked power, but I don’t think I trust any process which is supposed to ensure that the person with unchecked power is sufficiently competent. I don’t think Bells are sufficiently competent; they don’t seem to think about how their plans affect people on individual instead of population levels (see: ground rules almost forbidding violence-in-general, application of the ground rules which are known Joker-incompatible to an entire pre-inhabited Panem without a chance for somebody to go somewhere else, assuming that agreeing to meet somebody (or not even doing that) gives you permission to teleport inside their room, etc.), and both are important. I’m also not sure how to classify Pattern’s handling of Ganymede, which also seems negligent; assuming everybody in the population agrees then this is fine but assuming they don’t it would be trivial to ensure nobody actually was able to contact Pattern despite her attempts.
A Bell with unchecked power probably does better than any real system of governance, but that doesn’t mean it’s the best they could do with their resources. At the very least, everybody should have a means of getting in touch with her or her staff that isn’t as easy to take away as email, which not everybody has access to, or
a literal piece of paper which could be lost or stolen.
Also given unchecked power, the choice of “Earth and all its problems, Saturn and all its problems, or being a personal friend of the Empress” is not the best that’s possible. Pattern’s been out of contact for a long time with multiple Jokers available;
she should have a way for people to secede from both if they want.
As Jalapeno points out directly above, there’s also the local maximum problem. Rose started with much-less-than-unchecked power, and started improving things a lot, but doesn’t seem to have changed her strategy much when given wishing
even when given other Bells as examples. I don’t think she’s laid ground rules, there hasn’t been any mention of her going to countries that she couldn’t have reached without minting, I don’t think she’s even done anything about the
social structures that caused her to need to go into the Witchwood in the first place (“If it weren't for the fact that he's the local lawman, she wouldn't even be allowed out into town on her own” and “orphaned seventeen-year-old girls tend to find it in their own best interest to get married, and if she wanted to get married”).
I’m not aware of any problems with Bell-and-Maitimo joint rulership, except for Midnight-related blind spots, but we haven’t seen that in as much detail. I think usurping the totalitarian empire with birdpeople might have been the wrong move, but we don’t have enough details to know for sure. I’m curious what Steel would say about it.
* Assuming “competent” also includes reasonable goals. You could be the best at running a country/planet/world how you like and just not care about the wellbeing of your citizens, but I’m just grabbing all of that for “competent”.