I've been a huge contributor to my current company, but as the first employee, even 3% of our stock feels stingy. I've easily contributed more than a high-equity founder (by everyone, including other cofounders', assessment). Also going through the "well, we can't pay you more because we can't afford it" rigmarole and not even getting the title consolation prize. Similarly feeling trapped by the whole mess.
I frankly think it was a poor decision for me to join the company, and I can't see myself taking another early employee position unless it's fully compensated (either much more equity than is traditional, or a market salary), which doesn't seem to be the norm, despite outsized risk.
I've found consulting to be a good outlet for ambition and way to make up for disappointing compensation. I also enjoy working on side projects with the intent of commercializing them.