I am not a fan of speedruns because half the (PUG, whether premade or DF) groups can't manage them properly and would have taken less time to do it the normal way. So I don't bother. Instead I just do AK for the 150 myth I need to cap after I am done with Coil 1-4; it means I have to run it 4 times per week, really not that big of a deal. If I feel the need for variety I'll do Garuda HM; it's roughly 5 min, so 4 of those take less time than an AK run and net the same amount of myths.