By and large, it's an extremely impressive re-creation, and I'd say 99.98% true to time period, with most inaccuracies having to do with the Titanium Client.
Like others have said, I do recall resists being significantly more useful on live in this era. My guild spent a fair amount of time doing Velious content, (granted, a lot of that was during the Luclin timeframe, because Good team was so far behind Evil & Neutral on Sullon Zek) and I remember very clearly that having 200+ resist practically made you immune to fear and DD AE's from dragons, as long as you were 59 or 60. 250 resist and level 60, it was like a 2% chance that Fears & Normal AE's would land on you.
One other thing that a lot of people probably don't care about, but I'm 100% certain of, is being able to use duck to get into rocks/landscape for a LONG time, at LEAST through Velious, and I think even through all of Luclin. This was how I entered The Hole as a Good Team Ranger on Sullon Zek - I never got a Hole Key, I just rapid-ducked/strafed, and could get through. It was also really handy for staying safe as an under-geared melee when Wizards and Druids ruled the pvp servers (on newer servers, nobody has resist gear yet). It was also a dead give-away to show who was a cheater, when wizards run right up to you in the middle of freaking nowhere in Everfrost or Skyfire when you're invis inside a boulder. Anyway, most if not all "landscape" types of boulders and rocks could be entered that way, and as long as they were the type that had an overhang above your height, you could get in by ducking/strafing. There weren't restrictions on exiting either, you could walk right out, it was getting in that took just a little bit of practice.
Anyway, if I could fix just 1 thing to make it more "accurate", it would be tweaking the resists slightly. However, it's honestly probably good for the server that it's a little more "hard mode" with the resists the way they are...
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P1999 Blue: Relent Less - 60 Bard ; Red: Shifty - 24 Druid
Formerly: Toomuch Twohandle 65 Ranger on Sullon Zek

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