Are you still going to use vBulletin? If so, are you planning to upgrade the version?
3. I feel like at the top right corner here- https://imgur.com/a/7kdRCak? you could add like little video clips of replays or gameplay. Like a short clip plays- slides to the left or right vanishing and a new short clips play automatically.
4. At the corner where we have our name and stuff here: https://imgur.com/a/MBXx6ff You could definitely make this more customizable. What would be cool is to have like a bigger box and put our Current tori standing tall next to our name- with all our items on it- And if possible we can rotate that tori like on toribashtextures.com. You know what I mean?
5. As for the main frame of the forums you can totally change it. instead of having it in like order like 1. 2. 3. 4, like we have now. You can put them into box categories. And have like the "Toribash" section into one box, "help" section into another box, "market", "clans, etc into a separate box like this: https://imgur.com/a/4JSD2LY and then in each box background you can put a shade of a tori to make it look cool if you know what i mean.
Then after having all your boxes you will have plenty of space at the bottom- which can allow you guys to add advertisements to promote tb like: https://imgur.com/a/LrIEs8p
It would make the forum laggy and it'd take ages to load. I would put my focus on optimizing it and make it fast/bug free, while at the same time modernizing a bit the overall design. It doesn't need animations/cool effects/large HD images.

As long as it's lightweight and works... I'm glad that you're not going the way of unnecessary js/css animations(cancer for any older machine)
Will this change bring around https and perhaps some fixes to the out of date, and very vulnerable, php?
I guess what dare was meaning by ads would be event ads? But yeah I don't think anyone would like that.
Is there any possibility of users using external css? Or is that beyond vb's functionality?