I'm 49m and have been using Tretinoin (Retacnyl) for about 3 months now. I started with 0.025% and am now up to using 0.05% almost every day. Apart from a few pimples the first couple of weeks I haven't had any bad reactions and I think that my skin is looking a bit smoother already. I want to continue using it, but there are a few things I'm not sure about and would love your help.

1) Should I keep using 0.05% daily or should I eventually try to move up to using 0.1% daily? Is there an "end goal" for the best strength and timing for Tretinoin?

2) currently I'm using the Tretinoin all over my face except for right under the eyes as I have heard that the skin is more sensitive there. Is it safe to use Tretinoin under the eyes and is that something I should aim for so I eventually use it all over my face?

3) Is it safe to just keep using Tretinoin every day for many years or should I take some periods off once in a while?

Thank you for the help. :)