These are several methods , and I think one should keep in mind the fact - any heavy cleaning will wind up removing patina , period .
In my experience with such , I'd say that your items ought to be treated as if they have been 'smoke-damaged' , such as in 'survivors' of a house fire .
The industry standard , for cleaning , would be the VERY patient process (think of each piece as a potential week-or-two project) of repeated gentle cleaning cycles with cotton rags/q-tips + warm water + Orvus Wa (followed by a good dry-off) .
Orvus Wa is pretty much cow shampoo , and is often sold in 'cow-sized' quantites , but sometimes a local farm supply , or a janitorial supply hse will sell you just one jug .
After cleaning the pieces , then you could evaluate what these do-dads really look like & then decide about polishing &/or finishing them @ a later date .
IMO , if your items have not been 'burnished' (I can't tell from pics) , chances are that polishing them would make 'em look pretty sad .
