Please do not increase to 1500. If something needs a 1500 character explanation as to why it shouldn't be on the site, then it is probably controversial and you would better turn to meta to get a more detailed response from moderators and the community. You can include the key points needed in a flag explanation in a small number of characters. If there are many flags then the last thing I want to read is 1500 character essays on each of them. While I recognize that there may be situations where a longer and more detailed explanation could be provided, you can usually be detailed and specific without waxing over the minutia of why and what and how the particular comment or answer or question is offending or inappropriate, and without the need to take many minutes to write, read, and digest the whole point of the explanation which, in very good likelihood, could be contained within two or three sentences, but which, because I have 1500 characters available, I very much want to get my full "money's worth" and use every character available to me, recognizing that there will be a small number of cases in which I want to say more but which the unfortunate limit prevents me from doing so, and by the time I get to 1500 characters, which is now imminent, I feel there is little left for me to say except that you have wasted a minute or two of your time because I felt obligated, for the sake of all moderators reading flag comments, to provide that little bit of superfluous explanation.