As much as I think that moving them to the player selection screen is a great improvement to their own usability and keeps the Map Options (I still suggest to change this overly generic name to "Rules Options", as these options do not belong to the map, but to the xml, and pretty much whatever options for the map are "map options", comprising, like, how much you want to Zoom it) much cleaner, I definitely believe the main starting screen should not immediately offer options that are, either, marginal or, worse, AI only.
This assuming that the main way of playing TripleA is with no AI at all, any AI usage being never primary nor standard, but at most an alternative way of playing the game (and I still see that the tooltip of "Play Online" tells me so). It is just common sense not seeing on main screen things that are not primary.
Of course, as I said, moving to the player selection is the way to go (much better than having it in Options), for several reason I think we all see, hence my primary (first best) suggestion, would be to make these options AI only and appearing only for players specifically assigned to an AI.
This means that nothing at all would change, from the current stable, if you are selecting a game with no default AI players (you won't even see the new column), but the additional column will appear, with the thing next to the AI selected players only, only when you select players for AI, looking like this:
The things on the right, with the "100" default, would be there for AI players, or appear when you select an AI, and disappear if you select Human, while the "Income %" column would totally disappear when none of them is showing.
As you can notice, I also agree with all @Frostion's adjustments, except that I would put the Income column closer and call it "Income %", not having the percent symbol right of each thing.
If you don't agree with this proposal, and would want any part of the "Income %" (or whatever it's called) showing up always, then I surely say that this option should be not AI related at all (but working for players assigned to Human too), as I surely believe it would be bad something AI only showing up as default, especially since players are "Human" default, and should stay so (plus, if you can set it while the player being Human, it would be confusing if, then, it doesn't work).
Yet, assuming that my proposal of having any part of the Income % tab magically appearing only upon assigning some to AI is feasible and accepted, then I would have little doubt in affirming that this new feature should be limited to AI only (which would be assured as default, if following my proposal of the things appearing only right to players that are assigned to an AI).
The user-oriented main reason might be what @Black_Elk is saying, to use it as a less distortive alternative to rebalancing maps by bidding but, honestly, I don't think this usage will become popular, or, at least, I can't see people starting to do that, instead of bidding, once they can. Since, anyway, in such cases, I think it would make sense to have more of a boardgame feeling, I think this might have an actual popular following (but I still doubt) only for something being a flat bonus (like giving +4 production each round to Russians, or whatever, instead of a bid, but not a percentage, like I'm seeing here).
The user-oriented other reason I can see, for wanting the Income % option, would be for playing a map with your little brother, or something, giving him a bit more income, just to make the game some less unfair; honestly, I see uses like this one so marginal, that I would not support them, just because of how unimportant they are and, in my opinion, I would rather give some bid.
The maker-oriented main (or rather only) reason I can see is to have, like, a player that it is more productive than the average, and manages to get 50% more the income out of the same land, than another one. I guess some mapmakers might use a feature like this to represent more efficient civilizations, like the Germans getting a few more income per territory than the Italians (so, like, you prefer that the Germans take "Ukraine SSR", instead of the Italians), or the Americans making much more income per territory than the Chinese, out of the same territory. While this might feel totally rad, I'm actually thinking I'd skip it, as it would really just not jive with its normal usage as, then, you would have all of a series of bonuses assigned, and no way to add percentage AI bonuses on top of them, thus it would just make it confusing to use them for what they are primarily intended for (for example, if you want to give +25% to all AI, and you are dealing with a game with such bonuses already assigned default, for not AI reasons, you would need to think and calculate in terms of how to add this general 25% on top on the normal ones, and would be just weird.
To sum it up, if something is meant to be almost only for AI, I would help myself cutting confusion by making it actually AI only (and, of course, then it should be not possible to assign it ineffectively, or it would be even more confusing).
The alternate not-AI use of making some players themselves more productive than others is of arguable interest, but, to cut confusion, I believe it should be rather handled with another similar set of settings, not for the AI and located in the normal options, where you can have a +25% for Germans, and you can, then, still give a +25% AI bonus to them too, that would be calculated based on the income already multiplied by 1.25. Such a feature is arguably not much needed, anyways, since you can do about the same by just having some players having lower production costs for the same units (for example, in LOTR, the Goblins can buy the stabbers, that are the same as the orcs, but cost 2 instead of 3, plus have the even better shooter, making the Goblins by far the most efficiently productive civilization in that world, already), or having better units in their frontiers, also since this would feel like something you would want to relate to tech advancement, and there is no way to change properties settings, not even with triggers (thus, having the possibility of saying that a player is inherently +25% productive, or something, should be rather handled not by unrestricting the option to AI, but having a similar option not in the properties at all, but in the playerAttachments (that you would be also able to change with triggers)).
So, my definite suggestion is for these options to be AI only, but only as long as they are totally absent from main screen, when no AI is selected; otherwise, just as a matter of principle of not having AI-only options showing up at all as default, I'm definitely for them being not AI related at all, if I have to see them all the times.
Regarding the bids, just let them where they are, especially if following my suggestions here, and having this stuff AI only (while not the bids). No good enough reasons to risk disrupting the intended options listing of many maps and, in general, when in doubt about a change to something stable, don't change it. Plus, I would really not add any more columns in the player selection.