I'm only playing on Normal. Without Ironman. I'm still kinda scared of Chrysalids, even with my MEC troopers. I'm actually glad I picked up Enemy Within. It totally feels worth it. I might do Classic someday, when the pain of losing Majors and Colonels to stupid decisions has been numbed sufficiently.
Speaking of Chrysalids...
This mission was so freaking intense. It was amazing. At first, I didn't know what to expect in the infested town, but when I found zombies, I put two and two together and figured that it was a Chrysalid mission.
It actually proceeded pretty smoothly for most of the first half of the mission. Thankfully, there was no timer for the first half anyway, because as soon as I realized that Chrysalids were everywhere, I slowed my pace down to a crawl and put Overwatch on everything. Unfortunately, just before I breached the large ship at the end of the docks, I accidentally triggered a set of Chrysalids in the corner of one of the last of the smaller boats. Normally, it wouldn't be that big of a deal, except that I triggered them with the last soldier of my turn, resulting in a dead sniper. It wasn't that big of a loss, because the sniper didn't have Squadsight or many abilities, but it was enough to throw me off balance.
The real test came after breaching the ship. A fucking Chrysalid nest-whale. Both of my MECs were equipped with the kinetic punchers, so I wasn't too worried until one of my MECs was at 1 health, and the other at half health, plus a soldier who most certainly would die if a Chrysalid got to him. I basically camped the whale for a little while, punching Chrysalids wherever I could and reloading ammo when possible while a soldier on top turned on the ship's transponder.
With the transponder turned on, shit got real, fast. With the timer ticking and my entire force generally unlikely to take a single Chrysalid hit, I had to stagger my squad's movement back across the docks to the ship before all hell broke loose on the town. I actually came close to losing another squad member twice or three times. Although, partly, that's not too much my fault (78% chance to hit? Yeah right!). Actually, I have to thank Firaxis for the movement system. With the two-move system, even if a Chrysalid ends up two tiles away on its first move, it can't attack you because it has to use its second move. I'm pretty sure that saved two of my squad members.
Right near the end, there were like 5-8 Chrysalids out on the field and two right in the general vicinity of my troops. I managed to eliminate one with regular gunfire, but my second MEC was out of ammo on its chaingun with a Chrysalid right next to it, so I almost used my kinetic punch. Almost. My sniper actually pulled out a regular ol' pistol, got some distance, and miraculously managed to get the 2 damage necessary to take it down, freeing the MEC to run away and reload.
I actually managed to get out all my surviving troops (minus one dead sniper) just barely on the last turn. I wasn't sure if my heavy would make it, either. If my other sniper hadn't gotten that lucky pistol shot, I'm not sure my chaingun MEC would've been able to make it out in time, either.
EDIT: It just occurred to me, but if we have Damage Roulette, why not make damage based on your Aim chances?