I barely use the slots I have, unfortunately. I have three characters I play with any sort of regularity and three more alts that I made during the small open windows after maintenance in case I ever needed them. And I've yet to touch the latter beyond getting them to 15ish - I can't even be bothered to log onto them to do the Mini Cactpots at the Saucer. 
So, my hat is off to those that can juggle more than a couple characters and keep them all going on various plots and whatnot. I just don't think I can split my time that many ways. I do have some questions, though, that I think may be important for pushing for this sort of change.
First and foremost: How many slots do you feel you need? I note that you have the idea of allowing people to buy more slots, as a way to incentivize it for SE as a new source of income. However, there would likely need to be a cap somewhere, right? So what upward cap would you want to have? 15? 20?
Which is important based on the second question: How many people do you think would partake in this process? There's a lot of reasons for this question, which weigh on both sides of the spectrum. If there's not enough interest in having the extra slots, SE may not feel it's worth the effort to add that level of functionality to the game when large percentage of players don't need more than the set amount (especially considering the "one character can be everything" setup, which could mean this matter is mostly for RPers - and then a smaller subset of said RPers who can successfully juggle 8+ characters).
If there's a huge amount of people who want to do this, then the cap would have to be set at something that won't unintentionally cause unforeseen problems. After all, if it's a popular enough thing, you could have thousands of people utilizing it adding thousands of new characters. Which very well COULD lead to an impact just from the extra character data being stored - and the changes needed to be made to allow for the purchase/addition of more character slots.
And there are the other, less seen factors. The housing one that immediately got brought up is a good one. If there's not a "per player" limit on housing (I don't believe there is), then that's going to tax an already strained resource - especially on servers like Balmung where it's already hard enough to get yourself your own little plot of land. And there could be other factors - maybe allowing that many more characters to run through the MSQ and dailies could flood more gil into the market or something. Or it could be abused by gil sellers who spend chump change in order create more characters to farm more gil for more cash. Not saying these are actual problems that could arise, but there might be difficulties and factors we don't currently see by adding the the character count.
So, my hat is off to those that can juggle more than a couple characters and keep them all going on various plots and whatnot. I just don't think I can split my time that many ways. I do have some questions, though, that I think may be important for pushing for this sort of change.
First and foremost: How many slots do you feel you need? I note that you have the idea of allowing people to buy more slots, as a way to incentivize it for SE as a new source of income. However, there would likely need to be a cap somewhere, right? So what upward cap would you want to have? 15? 20?
Which is important based on the second question: How many people do you think would partake in this process? There's a lot of reasons for this question, which weigh on both sides of the spectrum. If there's not enough interest in having the extra slots, SE may not feel it's worth the effort to add that level of functionality to the game when large percentage of players don't need more than the set amount (especially considering the "one character can be everything" setup, which could mean this matter is mostly for RPers - and then a smaller subset of said RPers who can successfully juggle 8+ characters).
If there's a huge amount of people who want to do this, then the cap would have to be set at something that won't unintentionally cause unforeseen problems. After all, if it's a popular enough thing, you could have thousands of people utilizing it adding thousands of new characters. Which very well COULD lead to an impact just from the extra character data being stored - and the changes needed to be made to allow for the purchase/addition of more character slots.
And there are the other, less seen factors. The housing one that immediately got brought up is a good one. If there's not a "per player" limit on housing (I don't believe there is), then that's going to tax an already strained resource - especially on servers like Balmung where it's already hard enough to get yourself your own little plot of land. And there could be other factors - maybe allowing that many more characters to run through the MSQ and dailies could flood more gil into the market or something. Or it could be abused by gil sellers who spend chump change in order create more characters to farm more gil for more cash. Not saying these are actual problems that could arise, but there might be difficulties and factors we don't currently see by adding the the character count.
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