All three are good games. They were my first cRPGs after finally beating Fallout 1 and 2 for the first time. Felt natural. I only played 1 because 2 came with a free copy of 1 and I was like well shit that means I gotta play it first right?
Wasteland 1 is great for its time but if you want to play it now and beat it under 80-100 hours or without restarting or retraining a bunch of Rangers, follow Per Joiner's guide.
Wasteland 2 Director's Cut was pretty decent. It felt like a soft-reboot seeing as it has a very similar plot to the first game and mostly rehashes those events but it's just a revenge story in a way.
Wasteland 3 is great. I want inXile to make more RPGs like this. Sure, it's got issues and blahblahblah shut the fuck up. It's fun, it's good, it's post-apocalyptic. I want inXile to make a Fallout game with Josh Sawyer now okay? I'm sorry, Josh, but hopefully this time people won't saying Obsidian is phoning it in and not giving a fuck :/