Depends a bit on just how wide ranges of limpers are. If these characters are all vpip between 40-100% with low pfr, then you can raise pretty wide. If, otoh, their pf stats are a bit more moderate and it's just a fluke that there are so many limpers, must be a bit more cautious. I'll assume the former (very loose-passive game) is closer to the truth in 3/6 live. And if I'm assuming correct, I think you're pretty close to optimal.
As a general rule I'm not crazy about the idea of raising small pp's in the scenarios you describe (numerous thread discussions on the topic). We label small pp's as "good multiway hands", and I feel like some people take that as justification to indiscriminately raisy-daisy multiway without really thinking. Yeah, you pump it into stove: a baby pp against five or six weak ranges is going to have a little more than its fair share of equity. But I feel the obv (that stove assumes you see the river) cannot be stressed enough.
Suppose you raise 33 pf, go 6- or 7-way to flop and the board is a K-9-4 rb. How far are you do you're willing to continue? Just an example to illustrate there will be hundreds of dry
boards you won't be able to proceed to river with, to say nothing of all the potential coordinated or even semi-coordinated or high-card boards you'll have to bail on the flop (or rarely turn) with baby pp's. By raising pf you might occasionally give yourself sufficient odds to see a turn, but rarely enough to see the river UI.
Basically I think the notion of a "value raise" with baby pp's multiway might be a bit of a myth, as it essentially requires hitting a set to win, but you're only gonna get to see 60-80% of the board most times (essentially only realizing 60-80% of your equity).
In short, I'm fine with what you're doing with pp's (maybe I raise 88).
sc's I think are a safer raise, as you know immediately on the flop whether you have a hand or a draw, and by raising pf you might make it OK for you to peel the flop for one with just some bd draws. In other words, you realize closer to your full pf hot-cold equity with sc`s. The flops you`re mostly folding are the ones where it was VERY obvious you don`t have a chance (e.g. you raise 6
and the flop is 9
Depending on just how loose ranges are, you could raise down to even 54s and probably 97s, imo. Not doing so is at worst a tiny error, though.
btw--I`m sure it goes without saying, but you need not at all feel obligated to cbet the flop in these scenarios.