I’m in the early stages of one of my own design, but have played through the RT campaign.
It’s very cool and thematic, and a lot of fun. The only slight drawbacks are firstly that it’s quite difficult for the starstriders to win - the ship map is tiny and so if you consider that close combat in general is favoured in Kill Team, this really puts the star striders back against the wall.
As the star striders player, you need to get a good grasp of the dozens of tactics options available to you as soon as possible. Most of your team is quite ineffectual without them. This makes them a complex team to play suitable for a seasoned player. You need to take down the 3 big guys as soon as possible, however the starstriders really struggle to wound them as they generally have weapons with low S and high AP - the worst combination against high T models with no armour, but invulnerable saves and feel no pain!
Your 3 key models as the star striders are Vane, the death cult assassin and Grell. Vane and the assassin have some special rules that once per game can cause mortal wounds or lots of damage, grell also does 2 damage per hit. Coordinated well, they’re your best chance to take down 1-2 of the big guys. In all 4 games I never managed to take down the leader though.
For the nurgle player things are rather more straightforward. Only a couple of guys have guns and you basically just need to pile in and get into combat ASAP (in two of the four missions, you need to block certain escape routes which actually means just getting in the way and waiting for the star striders to come to you!) from where your big guys will make mincemeat of most of the star striders.
In the end due to poor deployment in the final game by my opponent I actually managed to win the campaign, just (the campaign is decided by the final game only, and specifically whether Vane survives) but I doubt this would be easily repeated!
And that’s the second drawback really - each mission is narratively connected to the next and of course your teams are getting more seasoned each time, but there is no rules connection from one to the next and the final victory condition feels a bit... shallow? Simple? Hollow? If I played it again, I’d like a little more consequence depending on the outcome of each game (just a branching scenario choice would work) and some review of the final win condition. But that’s a big fundamental change to the campaign and honestly, the basic one in the book is still a lot of fun.
We were lucky enough to have a group of people that played kill team fairly regularly (3-4 times a month), and ended up adding a campaign-ifying our groups games. Experienced characters building up skills and somewhat managed mission profiles.
Not the depth/chewyness of necromunda. But good for low key gaming with mates