A concern was that you’d sink more ISO into championing a character than you would be simply selling the covers and using the ISO for something else.
Looking at OBW and ignoring all of the non-ISO rewards there are
22x 250 ISO rewards. 5500 ISO
4x 500 ISO rewards. 2000 ISO
10x 1000 ISO rewards. 10,000 ISO
This makes a total of 17,500 ISO
50x 250 ISO is 12,500 ISO, plus the 5000 ISO fee makes 17,500. So you break even.
However, in there is a load of HP, CP, covers and tokens that you get for free. So you don’t lose out. You get your investment back.
3* ISO
44x 500 ISO rewards. 22,000 ISO
14x 1000 ISO rewards. 14,000 ISO
10x 1500 ISO rewards. 15,000 ISO
2x 2000 ISO rewards. 4,000 ISO
1x 2500 ISO reward. 2,500 ISO
This makes a total of 57,500 ISO
100x 500 ISO is 50,000 ISO, plus the 7500 ISO fee makes 57,500. So you break even again.
And once more you get HP, legendary tokens, 4* covers and more for free.
I hadn’t seen anyone else do the maths on this. I can’t imagine I’m the first, but I’ve made a topic dedicated to it anyway. It’s a long term investment, if you want to look at it that way, but you don’t lose out as many (myself included) feared you would. I figured you’d spend, say, 50k in cover ISO to get only 40k back plus some extra stuff, but you break even in both 2* and 3* land. I’m not advanced enough to calculate 4* land yet, but I can’t imagine it’s any different.
[Edit for 5*]