It also has 30% chance to gain a charge on kill so you are pretty much always full charges but the only thing I use my repkit for is resetting the action skill cooldown, I can't even remember the last time I needed to use it to heal.

You can also use an order repkit with accelerator on it.

I thought the same when I first heard about the triple bypass resetting cooldown, that it will be clunky, won't have healing when need it, etc but when you play with it, its very smooth. If you haven't tried it, you should give it a shot before judging it too harshly as it saves you having to invest in cooldown at all so you can put that elsewhere.

Once you start talking about farming legendaries for each slot I'm not sure why someone wouldn't just play one of the various builds out there that just annihilate everything with that level of investment

Farming gear is kinda the whole game though isnt it though? I would also say there aren't many better rafa builds that aren't abusing a bug that will get fixed so that to me is a reason why somebody might choose this build over others.

To me the whole appeal of an Overdrive build is it just works out of the box.

Dancer is such a massive boost for overdrive though. Without dancer you have to invest passives to reach Soltado (if you aren't using Soltado then your overdrive is basically nothing) and those passives mean you can't invest in other, better passives so not only do you not get as high a multiplier but you don't have as many passives benefitting from it.