Schtick
I'm not very good at schtick. I tend to be rather shy, not very outgoing. Really, it's a miracle I'm in the SCA at all... but that's another story. However, schtick is one of the reasons I am still in the SCA. I joined the SCA almost six years ago. At that time, there was a lot of schtick going on. This was the time of the sheep trials and the balloon-dog defense, the first ARRG! with its battle between Jara and Windhaven for Ripon, the second ARRG! with the disappearance of Doctour Jock. As a recent acquaintance put it, I joined the SCA for the fencing; I stayed for the schtick.
Over the past few years, unfortunately, schtick in Northshield has faded. The Rapier-banter list is silent. There have not been any sheep trials or their like. Little time is spent developing personae and their relations with one another. This is disappointing; I really miss those earlier years. Oh, sure there are reasons for this decline. Those good at schtick have other obligations now; people have moved; mundane life interferes. Nevertheless, I miss it.
I saw a glimmer of hope, however, this past weekend, at Warriors & Warlords XIV. Otes brought to site several nerf blowguns. Almost immediately, Doc Jock organized an assault on the neighboring midrealm encampment. It was beautiful watching Mateo and Roland scamper for cover before the assault. It escalated after the assault. Sybil swiped the nerf darts. Jock kidnapped Miguel. Cookies and cordial appeared! A ransom note was delivered. A squirrel was kidnapped. Negotiations ensued. A squirrel was nearly hung! Booty was acquired.... That was fun. And beyond the fun, we met several new people - Miguel, Sybil, Janusch. (Marina we knew already.) Why has it become so difficult to have fun in the SCA these days?
Here are some rules for schtick, as stated by Mateo:
1) Never swipe essentials. (Food, fencing gear, sunblock (!) are out.)
2) Never, never go in someone's tent.
3) Stuffed animals make good hostages.
4) Play the game: an RBG is a "gun" even if it isn't loaded.
5) Have fun.

And the sheep trial lived quite long enough. Quite. :)
Part of the decline of schtick, I think, comes from what you cited: life, less play time, etc. However, I think there has also been a bit of fragmentation as well. Where we all used to camp together, or damn close to one another, and live in one another's common areas as much as our own, now I see more set groups - schools, households, and so on. Everyone is still welcome everywhere, of course, but there is also an obligation to hang with your own people back at camp at times. Less wandering and random persona interaction is happening, while more people sit and talk about their personas instead of getting up and playing them. Where we were all together in one club before (those rapier fighters), we are now in our own places and groups (with their own sub-focuses), each attached to rapier, but not central to it.
I am as guilty of this as some, and more so than others, so please don't think I am pointing fingers at anyone. I'm just looking at the landscape and trying to see the differences from what used to be, and trying to figure out how to back track a bit.
For one thing, a lot of us have, or have had, jobs in the SCA since then. That changes the game, sometimes for a while, sometimes for a long time, for some folks. We all used to be a bunch of steel swingin' geeks who just showed up and fought and occasionally held a stripey stick. Now that we got respectability and responsibility outside our immediate sandbox, it can and does impact our play.
Hey, it's a theory....
So, where has the schtick gone? It has left with other focuses and interests. It is a skill that must be practiced and honed. Unfortunately, many have never seen the real value of schtick, only seeing it as a way to entertain themselves until something better comes along.
Schtick does not necessarily have to be boisterous and loud. It is ideas and acts that can be delivered. Ulrich, I know you to be very quick of wit and that is the beginnings of schtick. The German thing is schtick, working with the quacksguild is schtick. Simply because you choose to support schtick rather than initiate it does not mean that you are not able to schtick.
Schtick is humor and a way of getting others to calm down. Channel that character idea that brought you into the SCA - almost assuredly not a duct-taped covered Super Duke, and play with it. Finc the things that you are comfortable doing and cultivate them. IN this way you can develop your own brand of schtick.
Look for opportunities to make light of a situation and do so. Practice doing and not just watching. Again, you don't have to be a big loud meat-head like me to schtick.
Doc