Just some thoughts after playing the preview content on Teyn and some of the dungeons and places in that area. This feedback concerns only the stuff that features dialogues and quests and generally what feels playable.
 

• The alchemist in fort Ancylis sells a complete master set of alchemical apparatus. As soon as I've seen it I knew I couldn't leave this area before buying all of the four pieces. Would be better if she sold only one master piece instead of all four of them.
• Basan-Dur has some nice loot if you venture down the lava chasm, feels like the Adventurer's Amulet would be best placed here instead of being in a random barrel at the south-west of Teyn. Only problem with the chasm is that there's a couple more dungeons in the same area that has the same "venture down an inescapable hole without  just to find a levitation potion or scroll that help you get back up"-thing going for them. It can be fine, but I think that a "good" player would venture down such holes only if they're packing some magic that can help them get back up (like the jump spell sold in the same dungeon, or by saving the levitation potions given to you in the archeology quest), otherwise it feels like an incentive for doing some save scumming. So what I'm saying is that this chasm is good by itself, it's something that calls for adventure, it's just that the other similar holes in the same area detract from this one. They're too near each other.
• About the archeological quest from the bookwriter in fort Ancylis, the quest seems ok in general but there's a couple of things that feel strange: why would the alchemist just gift you all that stuff? Would be fine if the Khajiit gave you an alchemical book to bring to her in order to trade it for the required potions. Also the nord priest being able to authenticate a very old nord axe on the spot felt a bit strange, feels like the smith could be a better candidate for the same role.
• About the same quest, finding the axe could be quite hard. It would be interesting if the axe had an enchantment and the priest explaining that nord weaponry of those raiding party being enchanted for frost damage (is it ok lore wise? I have no idea) this could make the potion loadout include some detect enchantment potions, finally giving some use to that spell effect!
• Rith-Ilviryon Ancestral Tomb. features another chasm to fall into, even if the orc warns you about the pit it feels quite strange to be completely trapped. I had to use a divine intervention scroll the first time around so I guess that the orc should give you a couple of divine intervention scrolls, one for you and one for the bosmer you're trying to rescue. In the end the bosmer will use his own scroll, of course, this is just to give you one to use in case you fall down the pit.
• The vampire stuff and the dungeon in general felt quite a bit high-level for a starting area but I guess it's fine. I was able to go through it as a very low-level character thanks to the engraved ring of wounding and the enchanted Veloth's stuff lying around the tomb. I think there's should be a couple more intdicators that this dungeon is best approached after some leveling from the player. Maybe adding a line to the orc dialogue about escaping a strong skeleton and then placing a skeleton champion just before the pit, in order to scare away very low level players.
• The biggest problem with the tomb is the loot. As I was saying, the magic-resistant robe and all the Veloth's stuff in the dungeon is quite enough to enable a low level character to complete it. Whle the rewards for the two quests feels appropriate the daedric falchion is a bit too much. It's weight could counterbalance the weapon but the selling price and the stats are way too good.
• On the coast east from the lighthous and Basan-Dur there's a crawl space that takes you to a collpased silver mine with a waterfall. This is another case of inescapable pit that is actually inescapable. The mix between pits that offer an escape solution and pits that actually traps you is quite strange. This feels like a very unfinished dungeon, though, so maybe it's just because there will be more to explore and a secondary exit. The waterfall looks nice though.
• The bar brawl is going to be it's own quest, right? For the thieves guild, maybe?
• In the end I think that this area works well for a new character, love the seyda neen call backs and parallelism, makes it interesting for veteran Morrowind players and newcomers alike.

The lighthous was very fun, it gave me the creeps. Well played!
I also loved exploring Rith-Ilviryon Ancestral Tomb, very maze-like and finding your way through itfelt like a real adventure.

edit: something I almost forgot about the ghost guardians in Rith-Ilviryon Ancestral Tomb. When killed the yellow enemy health bar goes back to full just before the ghosts disappear (could be a OpenMW thing) also the key dropped by the second ghost could be hard to find if not unreachable in the case players kill the ghost while in some weird position. Would be better manually placing the key in a chest or lying around somewhere.