I did a search for such a suggestion and did not see one so my apologies if it has been suggested before. 

I think it would be a cool idea to be able to nest contact groups inside other groups. For example:

>Chicago Contacts Group (Color Green) (Tag: CH)

----> The Loop Contacts Group (No Color) (No Tag)

-------->Kurgans Crew (No Color) (No Tag)

-------->Lancelot's Crew (No Color) (No Tag)

---->South Side Contacts Group (No Color) (No Tag)

-------->Senza's Crew (No Color) (No Tag)

-------->StripheGotti's Crew (Color Orange) (No Tag)

>Detroit Contacts Group (Color Purple) (Tag: DT)

---->Black Bottom (No Color) (No Tag)

Everything under Chicago Contacts Group will inherit: Color Green, Tag 'CH' (In above example) unless a specific tag or color is selected in the child groups. You are still responsible for setting up your own groups and naming them and adding to them, but you no longer have to add a person to multiple groups. Also if a crew changes cities you can drag and drop it to the correct parent group and all the colors and tags update.  Maybe I work with Active Directory too much but it just makes organizational sense to me. 

I really like this idea <.< mostly because it would just make life a bit easier and more organized than how current contacts are done, might make things less cluttered as well!

I must say I do hate the long list of contacts I have, can be quite the nightmare.

Have some contacts Nested, especially when grouping cities together would be so much easier. Not sure how the 'Add to contacts' button would work on profiles though as sometimes I have trouble clicking the right contact group. I would also prefer if the checkbox was a little bigger so I don't keep misclicking.

:D

Artus, good point, perhaps it (The Add to Contacts button on profiles) only lists the top level parent contact groups and responsively fits it to the box so that you have larger options to click on. When you click on a top level group, the others might disappear and you are left with the top level (That you chose, and can use to go back) and the child levels underneath?

Good thing to consider and work out. 

Is there any chance of implementing this for the OCD folk around here?

Its been 2 years and i still really enjoy this idea, i think we might have to get some more attention to it though for it to be considered?

+1 from me!

+1 like this idea.

I personally don't use contacts too much but I think this would be helpful to other users. +1