Hey, thank you for the kind words ^^ and sorry for the late reply.
No circuit wiring is intended but definitely very annoying in this circumstance. Under the hood it functions the same as a furnace and recycler, it's a crafting machine that picks its own recipe. Neither of those two are able to be circuit wired and I don't know if mods can even allow circuit wiring them without much hassle.
How many items inserters put into refinery is governed by the automated insertion limit. You can refer to the wiki page on this. As far as I've seen it's 2 - the minimum - on most of the refining recipes. Inserters can bypass this were you to have one that has stack size of more than 2, so even a fast inserter could put 5 items in a refinery that'll be inactive for long - when it drops to 1, that's below insertion limit so inserter swings for 4 more.
I think I'm able to change that insertion limit and I'll make it go down to 1 for long recipes. I'll check if 0 is also possible, since having a few seconds of downtime for something which takes minutes to refine is probably still ideal. For now set inserter stack size to 1 if you haven't already.
I'll cover the change in the next mod update hopefully within the next few days. I've been busy :(