I’d honestly say that having more senior admins would be better for the server. I think having more people earn the rank - and I do mean earn it - would look good on the admin team and the server as a whole. I don’t see why the senior window shouldn’t be open full time, and I don’t think your statement about the server having a problem with titles and power is a fair assessment at all.
I have to acknowledge you are more aware of the current situation than I am, but I am basing this on my (fair share of) experience with the server and what it means to have a power hierarchy.
You would never see a police force with 10 chiefs and 3 constables, it doesn't make sense. Generally, those with more experience and power are fewer, and their job is to oversee and manage those below them.
If I were to pick an ideal ratio arbitrarily, I'd go for something like 1:5. Having more Senior Admins than Admins makes the role redundant IMO, and I feel it exacerbates the historical issue the server has had with titles and power, though I give you the benefit of the doubt that it is not as big of an issue.