Regarding the firewall configuration, it would be advantageous to segregate the ports using commas. Presently, in order to facilitate TF2 gameplay, it is necessary to generate seven distinct rules instead of a singular rule to forward the following ports: 8080, 9012, 1234, 9001, 9002, and 23000-23999.
It would be highly convenient to incorporate a button that enables the mass update of all packages. Currently, the procedure necessitates the repetitive clicking of individual updates, which can be quite tedious and uninteresting.
Upgrading packages (via the CLI opkg upgrade command or the LuCI Upgrade... button) can result in major problems. It is generally highly discouraged, unless you know what you are doing or if there is specific instruction to do so.
The topic of some sort of warning text and/or technical measures that would require the an additional step (an "are you sure" button) has come up in the past. In fact, I believe I was one of the people asking how such a thing might be implemented. In the end, it didn't get much support (and there may have been some objections). Since I'm not a developer, I would need to convince others that this is an important enough change to warrant the time and energy necessary to implement it, which I wasn't able to do. That said, it's been a few years, so feel free to raise it again -- it is possible that opinions have changed on this topic.
Opkg isn't good enough at handling dependency conflicts to be trusted in a fully automated process. I know from the number of times I trashed my installation doing just what you suggest. Not to mention jffs2 partition will quickly fill up by updating root libraries (unless you're running something with storage space in spades).
IMO, you'd be much better off using attended sysupgrade with your custom package list. That way you get newest versions of everything baked in the ROM and you don't have to deal with aforementioned issues.