Thanks Kev,
You are the second person to actually name a hop you like for bitterness additions.
My rule is to only ever use a hop that I'm happy to taste. Even bittering hops contribute to flavour in my experience so I won't often use higher aa% bittering hops, no matter how clean they reportedly are, just to save a few dollars. I will use them where their flavour and any other character might be appropriate.
Therefore German type beers get nobles as do belgians (which also often get styrians) UKs get fuggles, challenger and ekg (and styrians) with the occasional bit of first gold or target but less often.
APAs will get higher aa hops like chinook if I want a bit of pine resin in there but I've done some that are all cascade too. Chinook (or other piney hop) will still appear later. Same as when I've used centennial or less often citra and simcoe.
Aussie beers might get a small PoR addition at 60 only (or a split of cluster and PoR) and I can guarantee there is a flavour contribution.
Sour/funked beers closer to 20
Bitterness range for me depends entirely on the beer I'm brewing and what's in the grist. I've brewed everything from 15-17 IBU hefes to APA type things around 60. I'm not a super 'let's chuck loads of hops at things kind of guy though so I haven't tried to push much beyond 60. I have plans for a UK barley wine that might push further but age will also mellow that considerably.
Any hop I'm happy to taste in the final beer, I'm happy to use for bittering.
Bitterness levels for most of my brewing:
Tripels 35 - 40
ESB 35 - 50
APA 40 -60
Porter and stout 25 - 30
Saison and similar 30-40
Darker belgian 25-30
German lager 25 -35
All calculated by software, tinseth method, no actual testing (so might be bollocks) and made with non-adjusted no-chill.