Overall, I have to say that I like 8th better than 7th. In fact, I only played a few games in 7th and yes, I am one of those who really liked 5th edition. Specific game thoughts first, then overall 8th thoughts.
Anyway, It was against Grey Knights, but not a psycher list. Two dread Knights, 5 or 6 squads of troops, Drago, three Razorbacks, two flyers.
I had a BN and a Vanguard. Squad of warriors with a succubus in a raider, squad of wyches with a succubus in a raider, full squad of warriors in a raider, two ravagers, razorwing, 5 Incubi in a venom, archon in a venom, five warriors in a venom, extra venom from one of the succubus. Everything that could carry a blaster did. Then there were the two squads of 5 mandrakes.
The deployment was the corners one, so no way to avoid his deep striking Knights. I got as much as I could out of line of site. He had everything on the board except drago in Razorbacks. He got first turn and deep struck the dread Knights on my left flank and luckily could not destroy my raider with the warriors and succubus, but got it down to 2 or 3 wounds left. He did nothing with his one razorback that had distance and line of sight. He ate half the wounds on the Razorwing with his flyers. He failed the charges with the dread knights. I stripped a few hull points off of the dread Knights with blisters. My Razorwing did zippo. My ravagers and other blasters (and Razorwing) managed to kill a flyer and strip a few razorback points. Then it got bloody. Ships blowing up. Wyches and a succubus in close combat with the dread knight. Warriors in close combat with a dread knight, while I kept pounding away at his Razorbacks and the troops that came out. Eventually the mandrakes came in and killed a squad of his troops and he sent drago after them. One squad of 5 tied up drago for two full turns, finally getting rid of that reroll he gives, while the other snuck to one of his rear objectives. We were eventually down to a few models. Fifth turn I sprinted to all four objectives and he was down to just drago and a razorback. I had a ravager, 2 mandrakes, a succubus, five Incubi, 4 warriors, a couple of venoms and an archon.
So some of my thought about DE after one game.
The succubus is a close combat beast as long as there is some support so she doesn't have to absorb everything. The mandrakes were surprisingly resilient and did very well. Don't know if that is an anomaly of the rolls or what. Incubi are good again, but without an invul they are still at the mercy of all the 3 and 4 AP Weapons. The Archon is okay but his main role in my game was another blaster. Wyches are okay again. Not great like in fifth but a solid CC choice...still have to watch over watch and I was lucky he didn't have pistols. Speaking of the succubus' blast pistol was a life saver against the dread Knights. Being able to shoot in CC was the main difference there.
Blasters and dark light is massive. Ravagers are very good and venoms are very survivable. I like that they don't degrade and I can hide them. Raiders are good, but they were not as resilient as the venom, but the gunboat is still a force to be reckoned with.
PfP is huge. No moral checks and plus one to hit (especially for succubus hanging out with wyches) are very helpful in CC which seems to be what the new edition drives you to.
I am still unpacking and have not found my scourges, sslyth or my grots yet, so could not try them out, but looking forward to it. That is something I didn't say a lot in 7th...
Overall I like 8th. The vehicle mechanics are nice and I really like degrading capabilities. The game is much faster and easier. There are DE specific choices they made that I hope get changed but in general we feel fast like we should.
I wish cover worked a bit better or more thematic, but understand, something had to be done. I like the new shooting to hit, wounding etc, but I prefer the comparative close combat to hit rolls, purely for thematic reasons. A good fighter should hit a bad fighter more easily than a better one.
It seems after one game that this is much more heavily slanted to getting us into CC. May be wrong since I didn't play a gun line army. Anyway, I am looking forward to getting more games in.