Of course, everybody has different manner of work. Apart from my love to the clean installations, just points from 2 to 7 are what interests me (and also to zip/rar the newly prepared installation together with its directory, and to put the archive in some safe place before the upload or anything - I omitted this). Everybody knows the other things. Why points 2 to 7?
1. To update the old file setup_options.php, adding the new options, setting them, and actually composing a new file (with all possible errors), is bigger work than to get the new file and to set up a few names, passwords, "yes" and "no".
2. The same is with the file bb_specials.php.
3. After point 4 you have PERFECT backup of your new forum with less work. Otherwise, it may happen to make correction after correction later and finally to receive a fully disfunctional BB, and THEN to be forced to start from the very beginning, HAVING NOTHING AT HAND! That's very unpleasant situation.
Let's picture. I began for example with miniBB 1.3 and updated further to 1.4, 1.5, 1.6, and am now with 1.7f (after passed also trough 1.7a,b,c,d and e). And I did all the updates like that - some files, some templates, some lines of code, some errors, some corrections, some this, some that - and I have now one mess of versions and files, called "forum" and working with some magic. (Do not forget that some people even ask what does the word "server" mean.) And now, after I already have the described "forum", I make the mess even bigger, putting in it PARTS of NEW VERSION.
No, thanks. I like your software and want it clean.
What if only one HDD (the same - with the forum) on the server crashes? From the very beginning.
What if the admin/owner deletes by chance 2 or 3 files on the server and between them setup_options.php? From the very beginning.
What if electricity pick appears in the server? From the very beginning.
What if your moderator have done all the things wrong last week (beeing in love, for example)? From the very beginning.
And where will be your options then? Nowhere.
I like my security more than 1-2 hours of my work on options and templates.
Yes, the sweetest point is 11. That's why I propose the other 10 above it.
Of course, all that is a matter of taste.