With the huge pops on Classic, Janitor could use a small buff.

[RubberRats]

So, funny story, I actually was going to set out to program mop bucket tracking into the PDA program, but it turns out it already does that. Can't say the same for garbage bins, though.
As for the other changes, the only one I can really say I'm a fan of is giving janitors utility belts (mostly since I already find myself rushing one roundstart) and letting the mop bucket actually hold mops. The others I feel would affect the way janitors clean in a way I'm not sure is positive overall.
If janitors being outgunned is specifically a Classic problem, there is nothing stopping you from just grabbing the Tsunami and blasting the floors clean. Of course, you might not be entirely satisfied with this answer. So I have a few more possible changes:

• Either make the number of janitor slots scale with the server population (So 4-5 janitors for a station with ~100 people), OR
  
• Make a new role, the Nanotrasen Sanitation Operative, available once the server population crosses a specific threshold. They spawn with a bunch of powerful, if gimmicky, cleaning tools (eg. a Signifier ripoff that shoots mini-Tsunami waves, an extendable throwing mop) and slightly expanded access compared to a normal janitor.
  

The second option may be less than serious.