Some things to consider, the actual profile edge is, from my research, is only about 1-2 inches of that 60% of the runner you're talking about. Everything else is the gradual transition from that profile edge up to your toe. That transition will get more aggressive or less depending on the length of your runner AND how much "toe" or "heel" you have. The less "toe" or "heel" you have the more aggressive/steep that transition curve will be.
Generally, this will make the skates less stable as you rock off that profile edge and it quickly transitions up to the toe. Think trying to keep an upside down pyramid balanced vs something shaped like a rocking chair. Now striding on a runner with less toe will fee easier, but IMHO, that's because you're not required to put as much power/effort into finishing your stride off, which will result in less power imparted into your stride and thus less speed. It's kind of like pedalling a bike on low gear vs a high gear. With a low gear, you have pedal more to get the same results, but each push is easier. Versus the power and effort required to do one push on a high gear.
IMHO, if you chop off your toes, there's a real possibility you'll end up losing power in your stride and make you less stable. The degree in which you're affected is, in part, dependant on the length of your runner. If you have large runners, this effect will be reduced. But in general, the effect will probably feel like you're skating on an even smaller radius than the profile you're using.
Coming from an old skate, if you haven't profiled your edges regularly, you were not only skating on a reduced toe with your old skates, you were probably skating on a way rounder profile. With each sharpening, skate runners tend to get gradually rounder.
For me, I like lots of toe. I like feeling the bite and power when I finish my stride. When a sharpener fucked up and shaved mine off, it made the runners unusable, because I have extremely small feet/runners and the net effect was extremely reduced stability and bite. Everyone has their own unique needs based on their body type, but just remember there's no such thing as a free lunch. There are always give and takes with each tweak. For me, it's about finding the setup in which you give up the least to gain the most. And that's going to be different for everyone.