^ Fully agree with Merc. In my case, I vary the procedure to this:
Pale Moon:
1: Turn on menu bar
2: Turn off the stupid bookmarks bar
3: Set the home page to something suitable for the user
4: Decide whether to leave DuckDuckGo as the default search engine or switch it to Google (depends on the user) (well, on my opinion of the user really)
5: Install AdBlock Lattitude
Firefox:
1: Turn on menu bar
2: Turn off the stupid bookmarks bar
3: Set the home page to something suitable for the user
4: No need to change the search page, it's already Google in every market except the USA.
5: I don't do anything else. There is a whole stack of stuff that Firefox needs to make it usable, but why bother? If the user has enough brain to come in out of the rain, she will be using PaleMoon anyway. If not, she will probably like Firefox, in which case that's not my problem.
For my own use, or for anyone I look after for love rather than money (family and etc.), I'll also set About:Config browser.tabs.closeButtons = 3, of course. In Firefox, I'll probably just tell then to use Pale Moon but I might stretch a point and install CTR.
On my own machines, I load Firefox down with all the crappy extensions I want once in a while; keep Pale Moon practically clean. Surf as routine with Pale Moon (also with real Opera and Sea Monkey, of course), just copy-paste addresses into Firefox if I want to do something weird like use a special-purpose extension.