[Making C4 more unique.]

In X1 it was practically just a better grenade that took a couple more time units. The low weight made it so there was no reason not to give a stick or two to all of your soldiers.

A simple solution would be making a C4 'secondary weapon' in how the new inventory will work instead of a belt item. A really powerful and more versatile single use grenade might not be too unbalanced, especially when you have to sacrifice a sidearm for it.
This would also limit how much you're able to blow up in a single ground mission. Which has pros and cons of it's own.

Alternatively, changing it so you can't throw it anymore would fix all of the problems it had too. It would still fill the roles of creating breaches, exposing hiding aliens, and knocking down buildings. It just wouldn't also double as a 'heavy' grenade.
It would still be possible to use it offensively by running up to the aliens and dropping it, but you'd probably lose the soldier as well.
I think it would be better as a belt item if this was done. Making it unthrowable and a secondary weapon would be too harsh on it.

Even more alternatively. Removing it entirely and giving C4's destructive abilities, maybe with lower damage, to the grenade launcher would force players to have a potentially very vulnerable soldier if they want the ability to blow up more than a 3x3 square.

[Xenonauts 2 - Strategic Scale]

Boosting up the number of aircraft, engineers, and scientists while keeping them the same would work perfectly.

Saying the Xenonauts are the elite, and also replacing the airstrike button with a more complex send local forces button like Sar1n said also sounds perfect to me.

So pretty much, I hardly have anything new to say. Sorry about that.

[Debating Xenonauts 2]

Yeah, I'd probably get Xenonauts 2.

As for what bugs me about Xenonauts, I was pretty sad you can't put a base in Antarctica like in UFO Defense.

I'm pretty sure it was because the map was 2D and flat, so think of this as more of a plea for a 3D globe.

[Xenonauts 2 - More Alien Aliens]

Yeah, Harridans need to ditch the whole sniper thing and become complete engineers. Caesans could probably pick the sniper rifle back up.

Not quite sure how you'd be able to rework them into being engineers, but I've got some probably pretty dumb suggestions for their looks.

Firstly, those hands and fingers need to go, having them be replaced by alien repair tools grafted to their arms would make the whole stuck inside the suit thing more obvious.

Legs need to be changed too, robotic ones with rolly balls instead of feet looks pretty cool in my head,

Torso and head are fine as they are.

[[V18 steam] Error when sending two Condors to the UFO.]

Recently i was playing and a UFO came near my base, i sent both of my Condors after it. One gets to it first and shoots it down into the ocean, the other one that reached it in the exact same time doesn't however. It then says the UFO escaped to space and the game crashes.