Switzerland's success is way, way more complicated than "being outside of the EU". Not getting bombed to bits in World War II, for example, definitely helped.
One man's "excessive regulation" is another man's security, too, such as the workers' rights laws passed by the EU (and, coincidentally, fought by the UK).
We live in an increasingly-connected world, and the EU is going to remain a huge part of the UK's life, In or Out. We're going to have to adopt similar legislation to the EU most of the time anyway if British businesses want to deal with EU countries. We're going to struggle to influence the world's largest trading bloc - we already struggle to influence the US. Heck, we can't even influence ourselves, thanks to our ridiculous voting system (which is arguably even worse than how the EU commissioners are appointed).
If the UK had a stronger economy, much stronger productivity figures, took an active lead on workers' and human rights issues, and had a workable voting system, then yes, maybe Brexit would make more sense. But right now, our only claim to fame is that we have a "not-bad" economy. We're behind the EU in many other areas.
After all,
what has the EU ever done for us?