A lot of questions.
First of all, yeah, certain characters will be using vulgar language in the game. It didn't yet come across that Enderal's doesn't take place in an Elves & Orks fantasy world with good and evil characters, and for me as a writer it just didn't make sense that a brigand intending to cut your throat will say things such as "Give me your purse now!" or "I will hit you with my axe!". Its said that writing has to "feel right", and for me this certainly doesn't. However, not every character is using vulgar language as, for example, most of the characters in Game of Thrones do.
Its just like in a real society - People who are educated don't use it. People who grew up in the gutters where things such as robbery, prostitution and fights are on the order of the day will. How, for example, are you supposed to feel the poverty, resignation and danger in a place where bandits talk as if they've spend the past 10 years reading Goethe and studying grammar?
Furthermore, it also gives us as a writer a way to make the characters more distinguishable and authentic.
It's a word that I find hard to believe even exists in their vocabulary. Have you already voiced everything or was VA done just for this scene just for the video? 
I can see where you're coming from! However, it
did exist in these days and you can be certain that people used it a lot. (Wiktionary says: It is usually considered to be first attested to around 1475, but it may be considerably older). Really, I think it just takes some time getting used to. As I mentioned before, we're not doing it just for the sake of doing it, it fullfills a purpose.
Enderal is an ambivalent world - It is beautiful and mysterious, a place for bards and poets, but at the same time dangerous, dark and violent. You could say, its more authentic. Maybe because we as developers also grew up a little and saw more of the world. Keep in mind that the universe Vyn was initially created when we were 15 yrs. old.
Now that was a wall of text, and I haven't even started answering the other questions yet. Just to sum it up: We understand that the usage of vulgar langauge might polarize a little, but it just felt "right" for the above mentioned reasons. It fullfills a purpose, and only the characters with a certain background do it. I can safely say that none of the main characters do, since it doesn't fit at all into their personality and background. Trust me, I believe that once you get into Enderals writing style, which is different from Nehrims, I think you will get into it. Of course, there will still be epic and poetic speeches.

I hope we could ease your concerns a little!
Let's move on to the other questions!
with recharge time displayed x3 and so on - I know it's WIP and all, but is this intended to be in the final version as well?
Yep, that was still WIP. We didn't start balancing the talents yet, so these recharge times will, of course, be different. Some might be the same, though, since leveling a talent to rank three should make it considerably stronger.
so I assume those will be possible to interact with to loot?
Of course! There will be a stain of molten, magic ice on the ground from where you can access the inventory of the deceased enemy. I should have shown that, my apologies.
On to the mage part - it looks like you are wearing thalmor robes?
Most of the set use unique visuals, but currently they're a placeholder graphic for a high-level mage set. But since they're pretty good looking, we might actually use them!
is very good. Possibly too good?
Yeah, there's always the risk of abilities being too powerful. We concepted and implemented a whole lot of talents which we then had to discard again due to them being way too powerful and too easy to exploit. But Manaimplosion (and the other manipulation talent, which you could get a glimpse at in Articy Draft

) are relatively easy to balance. You could add a condition that prevents these talents to be cast on bosses or you could reduce the time that they're paralyzed.
Currently, changing from novice-legendary in the vanilla game only alters hp/dmg output and monster armor, will this somehow be changed in Enderal?
Enderal will be a whole lot more challenging than Skyrim on the average difficulty, at least thats what we're aiming for. But of course, difficulty will be adjustable!
PS. On the subject of SkyUI and SKSE - since you sadly are not allowed to bake it in to the TC itself, can you make it compatible with Enderal perhaps? Since it's the same engine it shouldn't be too hard I guess?
Like Hazzmat said, it really does wonders with the vanilla UI.
No, thats no problem at all. You can use any graphic mods or interface mods that don't add a .esp to Skyrim. But we're actually already using an interface-mod similar to SkyUI. It makes organizing your inventory a whole lot more intuitive.
Maybe in the next vlog you could do the demonstrations outside in the daylight?
Yeah, a lot of people critized that! We'll show more exterior or brighter dungeons in the next episode.
So do you select a class at the beginning of the game? Are you limited to the skill options of your own class? I apologize if this was explained and I missed it. Please don't take this the wrong way, your English is excellent, but English is spoken in many countries with many accents, and sometimes the ear is just not attuned to a certain accent. If you would speak a bit more slowly, it would be easier to understand. Sometimes you spoke slowly but then started speaking more rapidly as your enthusiasm for a topic erupted. 
True, I have to work on that. Sometimes it just gets me!I really love to talk in front of an audience, however it is hard to keep the right pace if your audience is a webcam.
As for your question, you can select a class with your first memory point (The first perk/memory of a class is the "Unlock discipline"-memory) around 30 minutes into the game, after something happens to your character. You're not limited to the skills of your discipline, however, casting higher-leveled spells required a certain memory from the appropriate discipline-tree to be unlocked. Thats just our concept so far. We'll see how that plays, and we'll change it if it feels to limiting.
Woah, now that was a whole novel!
All the best,
Nicolas Samuel