So I am in a dilemma in that a recent publication literally has used up every (legible) character on this page. We have checked thoroughly and every single character is necessary and this many characters are unfortunately needed to avoid confusion (This is what happens when you try to combine several different theoretical areas together). We have also used up a bunch of symbols such as stars or dots. This question is not about how I should reduce the number of characters.
So right now I am thinking of using characters from outside of the European family, such as Japanese characters (Hiragana/Katagana) or Korean or Chinese. Of course, provided that these characters are simple enough. Some candidates include ひ, と, ㅈ, ㄹ, し, 十. Some of these characters are quite suitable and have simple pronunciations, although we are not thinking of pronouncing them in presentations.
But I have two concerns:
most conferences and journals have a "We only accept submission in English" rule: The submission must be written in English. Does this violate that policy?
does using these character violate some sort of implicit cultural norm in scientific writing and European/North American conferences so that we should avoid it?
Update:
Thanks for all the feedback. But most seem to focus on what other fonts I should try to use instead. Just as a clarification, in my area it is highly not uncommon for the papers to use many many symbols. Here is a mild recent example (not affiliated with these authors) and this one I saw that made me go "wow the notation is so nice!" (again, not affiliated). These seem to be conference submissions (around 10 pages). For full submission it can go up to 20-40 pages. So as you can imagine a symbol problem quickly arises.
I can't help if everything comes out like this. If you notice, it is easy find usage of thing such as $a^{i,j}_{k,l}$. k, and l are two agents from i and j graphs and a is just one possible variable out of many variables. So we are already making heavy use of super/subscripts. We use hats to denote estimated values so we are already there as well. We are also making use of mathcal, mathscr, mathbf, mathfrak, texttt, etc. to denote sets, graphs, matrices, special matrices and special conditions respectively. All extremely conventional usages.