How is a SAK not in that collection, you can't call yourself a knife collector or enthusiast without owning one in my opinion. It's the gold standard by which all others are judged by. With that being I say get a full size SAK and a small keychain one like the victorinox rambler as it majority of the things you want in an urban enviroment in a small SAK, small flat heat and phillips to fix small electronics, bottle opener, toothpick, tweezers, scissors, blade. I would say it pairs up nicely with any full size knife. As for the full size SAK I think a Cadet would do nicely, or a Recruit if you want something slim, if you want more of a multi-tool knife there are plenty of options out there.