I think the emojis of iOS actually pretty chic. Of course, except for a few exceptions. I have not come up with the idea to draw emojis myself yet. I've looked at Emojimore and they say that there are over 2000 emojis. So if you want to draw them all, i wish you allot of fun. Another problem would be for me, as I get the drawings in a Massanger like WhatsApp. I believe that it depends not on iOS but on the program, how the emojis are displayed. So you have to find a way for each program, how you can use your drawings.