Hi Peeter,
1) as far as I know, Texlive is a real pain to port and maintain (which is probably why the FPC / Dports is still stuck with the 2015 edition). I don't know what John has planned regarding this, but I think that we'll need a volunteer who to pick this up. It definitely is a very important package, though, and I'd imagine a volunteer would get as much help as possible.
2) Okular is another beast due to the many KDE dependencies it draws in. Eventually KDE stuff will need to be supported, I guess, but until then you could try Lumina's PDF viewer ("lumina-pdf") which is already ported. Do you need any specific features of Okular?
3) Hexchat is on my to-do list (wasn't exactly at the top, but I'm moving it up for you now). From a quick glance it looks like it's only missing one dependency.
4) Thunar and Xfce-terminal: I've started porting Xfce4 last month. 7 packages are available so far and my plan is to port the entire desktop. Thunar is next - however there are some dependencies missing currently (I need pull in HAL which I'm not too fond of...). I'll definitely get back to it, though. The terminal is low priority as there are already a lot of terminal emulators available. Xfce's panel is already available, BTW.
5) Chromium: I'm pretty pessimistic about this one. It requires several hundred (!) patches to build on FreeBSD (almost 600 currently and I've even seen > 1,000 IIRC...). Adding it will be a quite a job, but maintaining it is going to be a nightmare if we don't find anybody who volunteers to claim maintainership.
6) Newer versions of Firefox require Rust - and Rust is a story for itself. As far as I know there is work being done on porting Rust, but I have no idea when it will be ready or if it will succeed. We'll see.