Further feedback from my friends who play this for the first time:
UFO crash sites in general feel underwhelming difficulty wise after tougher cleaner missions.
Breaching UFOs doesn't feel intense enough in both gameplay and visual wise. They mentioned how lack of smoke, fire and debris made it look and feel a bit lacklustre and how it'd be cool to be able to blast through UFO walls and roofs. I did try to explain why it's not technically quite so easy to pull through, but they said even X1 had a mod that made it possible... I guess they have a point there..
Even though the first terror mission felt way too tough, the overall tactical difficulty doesn't seem to ramp up quite fast enough for them. They did a couple of observer crash sites and had no difficulties with zero casualties. Veteran difficulty for first timers it does feel quite easy.
They also mentioned crash site maps getting too large and boring. I have actually thought about this same issue too: as the UFO's get bigger, the maps should get smaller to avoid things getting stale/repetitive and having more focus on the new UFO type full of aliens and breaching it.
They mentioned geoscape gameplay being quite uneventful in general. Too few missions and UFOs. They wished there were more optional "side missions".
Overall they really liked the game and you got 2 new customers (+1 more potential buyer)