Nigel,
(I know that's not your name, it's just how I think of you - and you started it. If it bothers you, speak up. I also acknowledge I'm way off topic, but felt like saying hello, and maybe just talking a bit.)
I'm getting old(er) too, but rather than tired, I tend to think of it more as developing a better sense of priorities. Yes, time is money, and as you start running down on time (and hopefully, have more money...), time becomes much more precious.
You also raise an interesting (to me, anyway) contrast between working with electronics and wood. If you love electronics, or you're really good with them, or even just want to learn, then it can be worthwhile. None of that applies to me, however, and there are tons of people and companies (perhaps even entire countries...) out there who can put something together in a fraction of the time and cost that it would take me. Better yet, if they screw up, there's a good chance they'll fix or replace it for me.
But working with wood is much different, perhaps in too many ways to list: every piece is unique, it certainly smells better (except maybe that zebra stuff), it's more physical, more forgiving to some extent, and so forth. I don't actually do enough to call it a hobby, but aside from the typical bookshelf projects and such, in the last five years I've built (and designed) a number of acoustical sound traps and diffusers - that all pretty much work as intended, and some of them even look nice. Better yet, each time I get into one of these projects, it feels more like a vacation than anything else.
And yes, the materials are cheaper, you're more likely building something which is somehow unique to your particular needs, so maybe the time/cost tradeoff is different. But I also used to work on cars a lot when I was a kid, and I wouldn't even consider it today. Nowadays, I agonize (very briefly) over whether to vacumn/wash/wax/condition the leather myself, or pay someone else to do it - more quickly, with recylced water, and so forth. Maybe I'll spend 15 minutes touching up a few small spots they missed, but it seems like the right call to me.
Somehow, I don't think this is just a matter of age - the times themselves are changing, so to speak.
You're an interesting character, Nigel - nice to have you here.
Oh, and Mike: I was also a guitar player for almost 30 years, but you're never too old to learn where the good stuff is. If you enjoy playing and writing music as much as it sounds, I encourage you to think about whether you'd rather spend X number of hours doing so, vs. investigating the subtle differences between AC and DC :-)
No offense intended, I'm one of those people still using the battery testers that come with Duracells because I haven't quite progressed to buying myself a multimeter (but I'm thinking about it, really). Just fast-forward five or ten years and reflect on whether it was worth the gamble to maybe save yourself a few bucks instead of writing that great song you had in mind.
Welcome.
-Bob
