I got a Bosch 18v set in 2016, blue not green and just before brushless took off. DIY- its infrequent but intense use, as someone above said, jobs for relatives and friends as well as me. Very pleased. Batteries might not be quite as good 5 1/2 years on but no sign of needing to replace them yet.
Impact driver was a revalation, can be a bit fierce for some things in softwood (so I use the drill driver instead) but for most jobs, inclsuing fixing fence posts with coachbolts through concrete stubs they are brilliant.
Votage is a 'think about' decision - 18v is most common and will have more grunt than 10.5 or 14 - but capacity is simply a convenience thing. I think mine are 2 aH, so you need to stop and change battery twice as often as 4 aH, might make a difference on site but for an amateur like me its no bother and the lighter weight of the smaller battery is a bonus.
My discerning choice back then was the brand that Screwfix had the best deal on at the time, I'm sure Makita, DeWalt etc would have been just as good. I would just look at what Screwfix, Toolstation or similar are 'promoting' and do the same.