Ae and mabie can be done easy in the same day. Deffo do them, Ae is fab, my favourite trail. Mabie is nice but have done it load. There is a wealth if other trails around and in mabie forest but you would need someone to light the way.
Kirroughtree is nice but a fair drive, but I would rather go there than glentress.
The big country at glentrool is really lovely, not a singletrack fest but it’s such a nice ride on the right day.
The glentrool blue is really nice.
Don’t iss the cafe at Ae it’s just re opened and the guys who are running it are brill.
Dalbeattie is not my favourite but don’t let that put you off, you may love it.
Don’t rush about trying to fit in a million things, chill and do some riding don’t spend hrs in your car.
There are loads of natural trails around Dumfries that are great. Up to lowther from thornhill is a great ride.
Enjoy.