I would be fine with 3+15K+150K.
Mostly because that's where the sentiment seems to be going, and because honestly, I don't think there's a huge difference between starting with 3 lives and starting with 5. Even in DK I don't think starting with more lives makes as much of a difference as people think it does, since it doesn't much change the ratio of lives to boards. To reach 22-1 on 3+1, you have to clear 113 of the 116 boards on your first shot. To reach 22-1 on 6+1, you have to clear 110 of the 116 boards on your first shot. 97.5% vs. 94.8%. A+ vs. A. Either way, you're not gonna get there without the skillz. (This is NOT an argument for switching competition to 6+1, btw, it's just an observation. A few more lives makes getting through the game easier, but not *that* much easier, especially when you factor in the occasional total screwing.) 3+1 is more masochistic, and ensures that fewer runs will reach the end, but I'm convinced that masochism is part of the dark psychological underbelly of why we play this shit.
Anyway, Remix is probably slightly more screwing-prone than DK, but if you manage to crack 1M on Remix with 15K+150Kr, you'll have gotten SEVEN extra lives, which more than makes up for it. That's still super-lenient.
The only thing I don't like about going to 3+extras is that it moves us off of the defaults, and when you move off of defaults, people invariably use the wrong settings. But that's a pretty minor complaint.