Nog from DS9.
Utterly disappointed as I dislike the Ferengi even more than the impossible Klingons, and DS9 for me is the most unlikeable of all Star Trek series. I know NS rates it and I appreciate it is in many ways the most consistent of the shows - but likeable never.
As you may have seen elsewhere, I am rewatching The Original Series, which overall is my favourite. Despite there being a huge drop off in the quality of the stories in the 3rd series, it's the one for me that is the most likeable and has my favourite character.
The Next Generation has some good stuff but is very patchy, and had a number of characters I found tedious, and yes, Wesley Crusher, I'm mainly looking at you.
Voyager is even worse for boring characters (Neelix wins out there in a crowded field), and is only really saved by the EMH and Seven of Nine.
Never managed to get interested in Enterprise. And Discovery and Picard don't seem to work for me.