Congratulations on dropping all that weight. If that isn't deserving of a bike present to one's self, I am not sure what is.

Just to introduce a different idea: Have you considered a so-called gravel bike? Basically a road bike that is very capable on trails. This would give you the lightness and speed you crave. Some versions come with modest suspension too, if you feel you need it.

I just saw this last night: https://opencycle.com/wide

There are many, many other options now. Some are even quite affordable.