Here’s a proposition:
It’s reasonable for a player to defer pulling for shiny heroes until s/he has amassed something like the equivalent of 1827 TC2 feeders to enable a rapid levelling of a non-costume 5* from the beginning of 1/1 and right up to the end of 2LB and to 4/90. Breathe!
So, for a non-costume hero:
Going from level 1/1 to 4/80 costs 353584 xp,
then:
and
(353584 + 76730 = 430294) + 82500 = 512794 xp, + any extra xp that may be surplus to maxing each ascension.
TC2 produces non-trainer 1* and 2* (feeder) heroes:
Presuming TC2 will produce an equal proportion of 1* and 2* feeders and an equal proportion of feeders across colours, then:
feeders from TC2 will yield an average of 280.8xp per feeder
((150 * 4) + 180) + ((390 * 4) + 468)) / 10 = 280.8.
So, to take a non-costume legendary hero from the beginning of 1/1:
to 4/80 (with, at least, 353584 xp) will require ~1260 TC2 feeders;
353584/280.8=1259.2022792
to 4/85 (with, at least, 430294 xp) will require ~1533 TC2 feeders;
430294/280.8=1532.38603989
to 4/90 (with, at least, 512794 xp) will require ~1827 TC2 feeders.
512794/280.8=1826.18945869
So that’s the maths.
Meanwhile, my idea is to store up tokens. coins, and gems until I’ve got at least enough stored feeders to get a 5* completely levelled up.
I’d probably like more. If I make a whole load of pulls at the same time, along with a levelling hero I want to prioritise, I may also get a beta hero (potentially such as a HotM or similar) that I may also want to simultaneously work on. Any beta hero can be fed colour for colour while any pucka shiny could be fed with all others.
That’s a potential plan, but it may all be postponed when I use my keys in the costume chamber. In this case I may also splurge on token, coin and gem pulls as well and go back for a bit more colour for colour feeding, but I like the idea of saving up for a fast levelling. (Maintaining stocks of food and recruits can also enable timely 2* feeder generation from HA4). Waiting until you have necessary ascension items may also help.
How does all this sound? What plans do you follow when pulling for heroes?