One thing that happens when you attempt to play with other musicians is you became acutely aware of your own weaknesses. I've often let this awareness lead to frustration and discouragement to the point where I've either temporarily lost my inspiration to play or I've avoided playing with others altogether. However, another way to look at it is when you discover difficulties or limitations, treat these as areas to improve.
In my case I have a very long list of areas to improve. The two most prominent areas are:
--I've never, ever, played anything by ear. Not even Happy Birthday or Twinkle Twinkle Little Star. Everything I've ever played has been played from reading the tab. If I've ever played anything without looking at the tab it was because I memorized the tab and not because I was improvising or playing from within or whatever.
--I have absolutely no idea how to solo over chord changes. For starters, I wouldn't know what the chords were unless they were written down or someone told me. But even if I had the chord changes, I'd have no idea of how to improvise over them.
These weaknesses are because I have never spent any time on scales or exercises or developing my ear. I picked up tab reading pretty quickly, that came easy to me, so I just started in on playing tunes from tab and completely skipped over the fundamentals. I'm over four years into playing now and I'm realizing that if I am going to get serious about improving, or be able to play with others, I am going to have to change my approach and really work on some things.
Here are some things I want to work on:
Chord Tone Scale (CTS)
Peter Martin has some information and exercises available for the Chord Tone Scale or CTS. CTS is basically taking the notes of the scale and playing them so that you are always hitting a note of the chord on the downbeat. The trick to doing so is that if you are going from Low to High you leave out the 6th note of the scale (note E in the key of G for example) and if you are going from High to Low you leave out the 7th note of the scale (note F# in the key of G). He's developed some exercises around CTS and I hope that by working on that I'll be able to improve my ability to solo over chord changes. I have at least one other book with information of a similar nature so I intend to study that as well. And while I'm doing these exercises I want to really concentrate and think about each note and its placement - what its role is in the scale and why it's being used where it is.
I feel like my backup abilities have improved slightly since getting a banjo uke, but I still have a long, long way to go. I want to work on some exercises and learn various ways to backup a tune, different patterns and rhythms and techniques. I have some good instruction materials in this area and it's just a matter of applying those concepts. For example, jig rhythm is rather hard to play. But with some practice I'm sure I can improve even if it's just by doing some arpeggio related cross picking type stuff.
Three times through is the standard amount of times through a tune, especially for a tune set. I want to take Arkansas Traveler/Soldier's Joy and work up variations so that every time through each tune I'm playing it a little differently. I have some material directly related to these two tunes that should help. Then after having done that for these two tunes, I'd like to take some other tunes and come up with variations on my own. This will of course be composed improv, but once I get a better understanding of the technique behind the variations, I should be better able to apply that on the spot to anything I am playing.
I want to experiment with chord substitutions, such as when to replace a chord with its relative minor. I also would like to learn more about the chords used within a key, and why they are the way they are. Further, I'd like to experiment with the construction of those chords by combining different notes with the one and five chord tones to add to the expression possibilities. And lastly I'd like to work on partial chords, such as diads or drones, which hint at the chord but are kinda modal. Plus other stuff I don't even know about yet!
Constructing A Chord Solo
A couple tunes come mind (Memphis Flu, Ambiguity Song) for which I know the chord changes but I have no melody line to play. All I've been doing on these is strumming chords without playing any notes. What I'd like to do is take some of the CTS concepts I'll be learning and apply those to the chord changes, trying to build a solo that adheres to the chords being used. Again this would be a composed solo, but it would be a start.
Organize Irish and Oldtime Tunes
One other thing that I need to do, and this might be the most important thing to do in the short term, at least for my own preparedness, is to organize the tab for the Irish session and oldtime jam tunes that I've worked out so that I can have cheat sheets ready. This will allow me to be better equipped to participate should I attend a jam or session. I know that it's bogus to use the tab, but it sure makes it more fun for me than just sitting there not being able to contribute. If I can get those organized in time I might be able to attend the Rosie Connolly's jam this Wednesday or the Cary St. Cafe jam this Sunday.