I can only take this response to mean that running through caltrops in empty rooms is a common problem. There is only 1 mech that has more than 1 shield to start, and only 2 ways to get +1 shield: The level-up perk and the no shield for one floor challenge. So most people have only 1 shield for most of their run, and under this proposal would still get that one shield back after each room they clear. The only way they get hurt is if they are taking damage in empty rooms.
Anyway, I would actually be surprised if it is normal rooms that are the barrier to most players as opposed to bosses, where this change would have no impact. I don't know about anyone else, but I find the rooms vastly easier than Isaac, but bosses much harder.
*raises hand as one of those guys*
Find bosses often near trivial, but caltrops kill me. Especially the mazes of them you have to navigate in slow mode.
Also most mini-bosses are harder than the bosses, but have no health. (need their movement/bullet speeds nerfing, and HP increases?)
For the time being, I dont think the minibosses need changing. Honestly I think this is the first time I've heard someone say that they're harder than the actual bosses. I know I'm not the best judge of difficulty here, since as far as I'm concerned, basically everything is easy, but still, the minibosses are mostly free kills. Arcoris manages to smack me in the face with a quick bolt every now and then, but the others.... I actually think they need a buff. I cant remember the last time I took a hit from any of them. You should be using your sprint button during these fights.
On a total side note, that item that gives you +4 HP so long as you dont use missiles..... yyyyyyep, can die from that even if you've ended the floor, despite what it says. That.... might be an issue... ugh. That thing might need a couple of small changes actually.
Guardian blade (I think that's what it's called) REALLY needs a nerf too. Or should be the sort of item that is very rare (appearing in the second type of secret room only, perhaps). And the basic drones need to cost more. Double, I'd say. Bullet-cancelling items are a tad overly strong right now and it's too easy to get alot of them.