I wasn't really sure if I wanted to chime in on this, since the voting still ongoing and, as one of the nominees, I didn't want my motives for joining the discussion to be called into question. Ultimately, though, I decided it was worthwhile, since I've seen a mix of valid and... perhaps "overstated" concerns about the idea of monarchs also serving as Ambassadors. I'm going to express my personal opinion on the matter, but obviously, I'm also a potential candidate, so take what I'm saying with however many grains of salt you deem necessary.
The first criticism I've seen is that a monarch serving as an Ambassador represents an inherent conflict of interest; I don't believe this to be true, at least not to a further degree than it would be for almost any Ambassador. The truth is, the overwhelming majority of community members qualified to serve as Ambassadors are currently sworn to an established kingdom, and even among those who aren't (such as myself) many are still nobles in their own right with domains of their own to worry about. The issue of new players being greeted and assisted by people with a vested interest in recruiting for their own community is for all intents and purposes unavoidable, regardless of whether monarchs are "allowed" to serve as Ambassadors. I would hope the expectation of all Ambassadors would be that they not use their position for personal gain, as it goes against the very spirit of the initiative. If necessary, SBS could even make an official guideline to that effect, which I think would effectively eliminate any issue with regard to abuse of the position.
The second, which Dleatherus alluded to in his OP, is that having high-level backers serving as Ambassadors would be perceived as unfair, "pay-to-win," or an undesirable consolidation of influence; I'm not sure I agree with this, either. First off, as for the "P2W" argument, given that the position of Ambassador has, as far as we're currently aware, no real affect on the game itself, and is essentially a "meta-game" appointment, I don't think that being an Ambassador could by any stretch of the imagination be considered "winning." Second, it makes perfect sense that there would be a strong correlation between pledge level and fitness to be an Ambassador, and I would hope this would be obvious to newcomers. It's not that people are made Ambassadors because of their pledge level; it's that the people who dedicate the time and energy to this community to warrant being an Ambassador naturally are more likely to have backed monetarily. The two variables are influenced by the same outside factor: interest in and dedication to the game. I'd hope that newcomers would be able to see that it actually makes sense for certain monarchs to be qualified for such a position.
The third point I've seen made is the only one that I personally feel holds merit. Namely, that the time requirements of running an entire kingdom and serving as a public Ambassador are mutually incompatible. I can't say for certain whether this is true, but I think it's ultimately up to each nominee and the panel SBS puts together to determine how plausible juggling the two responsibilities might be. I do definitely see, however, that those who are most active in their own private communities do tend to be less active in the community-at-large, which is where Ambassadors are meant to shine. It's not just a shiny "Look at me, I'm special" badge; being an Ambassador is supposed to carry real expectations of active service to the general community. If one's time is dedicated mainly to managing their "own people," then that means less time left over to be a guide for newbies, which is ultimately what Ambassadors are meant to be.
In other words, I don't think that anyone's contributions to their own community should factor into the decision, because that's not the venue in which Ambassadors operate. It's great that they serve a similar role in their own private circles, but being an Ambassador means serving that role for everyone. As I said earlier, I think it's up to SBS and each individual candidate to assess whether they are able to maintain the public presence that being an Ambassador requires. If so, that's great. If not, there's no shame in turning the position down, or not being appointed. Ideally, the results of the voting shouldn't affect anything. The best candidates are the ones who serve as informal Ambassadors already.
I personally haven't voted for or against Adam (whom I sense most of this discussion is about) and don't plan to. I greatly respect him and his contributions, but I simply don't feel it's my place to decide whether he will be able to manage Vornair and be an active Ambassador at the same time. SBS knows him, and he knows himself, well enough to make that decision on their own. 👍