Comparing brokers side by side: how much does regulation actually matter vs spreads and rebates?

I’ve been mapping out a few brokers to compare, and I’m trying to figure out how to weight the different factors. There’s FP Markets that people mention here, plus a few others, but they’re all over the place when it comes to regulation, spreads, and rebate rates.

So here’s my real question: if I find a broker with great regulation and strong client protections, but their spreads are 0.3 pips higher than a competitor, how do I actually calculate what that costs me over time? And does the rebate from GlobeGain close that gap?

I keep hearing that regulation is supposed to be important, but I’m not sure if I’m supposed to treat it as a deal-breaker or more like a nice-to-have feature. Like, would you actually choose a less regulated broker if their spreads were significantly lower?

I’m trying to build a decision framework here instead of just guessing. How do you actually compare these factors without going in circles?