Currently, I'm feeding my starter with a 1:3:3 ratio with 20g of starter and 60g of bread flour and 60g of water. It's doubling in about 6 hours. When I fed with a 1:1:1 ratio, it peaked in around 3 hours. Is it better to feed with a higher ratio of starter to flour or is it the same?
Up to you, but with 1:1:1 you will have to refresh it very often!
With a 1:3:3, I'm refreshing 2 times a day. Can I say do 1:3:3 at night and then 1:1:1 at noon (15 hours later) when I want to bake?
Sure, why not! 1:3:3 should probably peak sooner than in 15 hours, but depends on your temperature etc.
As you already noted, the ratio certainly affects the time to peak.
Whether it has a noticeable effect beyond that, I believe depends on whether your starter is "young" i.e. consistently being fed promptly at its peak or not. For example, if the starter has been idle in the fridge for a month, then it is way past its peak, the food has run out long ago and the starter will be overly acidified. If you retain a large amount of that starter, i.e. feed at a low ratio like 1:1:1, then the resulting starter will still be very acidic. If you feed at a high ratio like 1:10:10, you are refreshing it by retaining much less of the acid from the old starter. It will of course take longer to peak compared to the 1:1:1 feeding.
On the other hand, if you are constantly feeding when the starter peaks and not much later, I'm not sure if there is any noticeable difference between, say, using it for baking after a 1:1:1 feeding versus a 1:2:2 or 1:3:3. Would be curious what others think though.