I havent used AGS, so my view is pretty biased, but I can give you my opinion on Visioniare.
With regards to your points, LUA is fully intergrated into the engine. If you look at Daedelic's games, you can get a pretty good idea of the more advanced scripting potential.
Resolution wise, you may be correct in Visioniare not handling lower resolutions properly. All of the games I have seen with it have been higher res-but thats really a place where it excells. STASIS runs at 720p, wide screen. At any one time I can have a few hundred frames of animation, particle effects, or video playing with no slowdown. As this discussion isnt an 'AGS vs Visioniare' one, but rather one focused on a modern engine, I think that handling high resolutions is a must.
I'm not sure how AGS handles scripting and in game events, but I can give you a quick rundown of how Visioniare does it. To quote: "that's a perfect opportunity to point out a big flaw: say I was to put a door in my game and I want to set it up so that a right-click open/closes it. All I do is name the door "door>v" and add a couple of lines of code, linking the door to a global variable.
That's all I ever need to do; even if the door starts out as locked, a right-click, which here produces "open door", will automatically fail since the door is locked."
In Visioniare, If I was to create a door, I would create an Object, and give it a Condition or True of False. True is OPEN, False is CLOSED. Then your command would be RIGHT CLICK -> If Condition = T, Close Door. RIGHT CLICK -> If Condition = F, Open Door. Visioniare treats each object as unique. There is no such thing as a 'Door' in the engine. There is just a defined area where you set up the commands for what happens when you interact in that area.
I used to keep a BASE LEVEL with all my different actions that I used often, but when you get into it it becomes really quick to set up interaction.
The templates and examples on the website really do let the engine down. Like I said, you really have to just muck around with it to figure it out. To set up something like a door proably takes about a minute, including linking any animations, etc.
I have had to use some workarounds for things that I'm sure AGS would probably be much easier for. For example, Visionaire doesn't support character dialogue portraits that dont 'pause' the game while you talk. As most of the conversations in STASIS take place over radio, I want you to still be able to walk around and talk - so I've had to come up with a way around that. But what it does have is very easily modified. For example, I have set up the dialogue engine to act as an in-game computer interface.
That said, Im sure that AGS does things really well that Visioniare doesnt, and visa versa. This really isnt a software debate, as those can never be won! When it comes to the things that a modern adventure engine should have however, I think that Visioniare is very progressive. Having the same built in codecs that VLC uses (so you can pretty much use any format for sound/video compression) opens up many doors. Having support for high resoution graphics, and being able to handle them is also something that a modern engine needs. But its the stuff on the horizon that really sets the engine apart. Multi platform support being a big one. If you were looking to create a commercial game, I think that that alone is a big enough deciding factor.