Yes, that's how all web applications work. I don't do modifications to the actual MyBB code though. Doing so can easily break things and also makes it much more difficult to handle updates.

I agree with you, an error in the PHP code can make inoperate the CMS.
By colors I mean : using colors with less black, with more of 65% luminosity, example for the Blue of the website (HXD) : 07C8FF
By interaction : Transparency (fading) animations, smooth transitions between pages, other font...
Example for board animation : http://codepen.io/codecalm/pen/wBgLYN
or for submit post : http://codepen.io/auginator/pen/oElzF or this: http://codepen.io/hakimel/pen/ZYRgwB
The interactivity make active the website so the users like navigating in the website,the popularity increase and the users visits increase also.
And for ergonomy, these (CSS3) transitions are integrated to the navigator,the speed navigation don't change so the users don't leave the website.

I suggest you to see some websites awards and new HTML and CSS features, they are awesome.

Do you have any idea what goes into making "smooth page transitions" work? It's not just a matter of adding in a CSS selector and being on your way. All of it requires sending data to the server via JavaScript (to put it simply) which means completely rewriting half of the code for the forum. It's just not going to happen. Like I said, MyBB is third party software and they maintain it.

Example :
<a href="private.php?action=send&amp;uid=32696" title="Send this user a private message" class="postbit_pm"><span>PM</span></a>
The animation will take only the place of the text <span>PM</span> ;all the links to the server by the CMS are preserved and not modified so the CMS can change it himself (PHP and MySQL) depending of the user without adressing to the animation.
The bridge between the page and the server aren't modified, only the bridge between the user and the page.
And for the colors, anything is stored in the CSS stylesheet, and it can be modified from the MyBB settings management.

Look, I'm trying to be polite here but I'm running out of ways to say this. The changes you want are simply not going to happen.

Your example there is literally adding a span to an existing link. Already that requires code edits but let's pretend for a second that it doesn't. What will doing that accomplish? It doesn't magically make the link animated. And even if it did, how will adding a 3 second animation to the word PM improve the user experience in any way?

Color-wise, the themes we have are the themes we're sticking with for the time being. The colors were chosen as they represent the different areas of the network and have been in use for years. On top of that, it really doesn't make sense to devote any significant time to re-skinning the forum when we'll have to do it all over again come MyBB 2.0.

Excuse me to have bothered you, I wasn't thinking that my change is impossible.
You can forget my suggestion and sorry for the disturbance.

Not sure whether this has been suggested before (probably has), but what about making a Discord server for real-time discussion of things going on with the site?

http://www.vg-resource.com/thread-28660.html

Could we possibly make the [tsricon] and [tsrgame] tags not require the url attribute? For instance if you just want to show an icon but not link it to anything, it would be handy if it's not too much work. Obviously the img attribute should still be mandatory though

There's no way to make attributes optional (in the sense that you can omit it entirely) but you don't have to fill in an actual URL. Enter # if you want it to still be "valid" without having to link it to something (that will just link it to the top of the current page) or just use url="" (I think that will work).

url="" works and just links to the same page, but it would be nicer if the icon wasn't clickable at all. No worries if it's not possible though, just a thought.

personally, i like them being clickable, but if i just needed to showcase the icon for judgement or something, then i can see where not linking at all would be useful

It's not possible to omit the entire attribute without changing the tag at which point we'd need to do something like [tsricon2] which also isn't optimal.

So I know that you can block a user to not see their posts (I think? I've never done it myself but I recall people mentioning it). I know this is probably a MyBB feature and not something you can change, but is it possible to do the same with threads? Just like block a thread so you don't see it on the forum?
If not, do we know whether it'll be possible with the upcoming MyBB update?

That wouldn't be possible without outside scripts. You can mark it as read and just not click on it, though.