Older stings are also harder to tune, specially if you migrate to different tunings - it's the early-stages of metal fatigue (strings are in motion when you play them, remember). Guitar strings are, effectively, elastic, and have a memory. This is why they take time to settle when first brought to tension, and also when you change from say standard to DADGAD.

I use the 'twice round the peg then thread' method (three times - neatly, on the post - for 12 or less, 1.5 for more than 50 - they'll get another wind when I start turning the peg).

I pull the string up tight before I start winding and keep the tension on while threading too. As the strings comes to tension I also pull, as hard as I can - (one method is to hold the string in your fist and dangle-bounce the guitar from it - you'll never be able to pull as hard as the winder). Bernard's advice about the position of the ball is key too.

I'd never, myself, restring just before a gig - though Napper often did (boy is HE fast)! The difference is that his strings stayed put once on (paired strings are also more forgiving - you just get a nice chorus effect), whereas mine had to cope with four or more different tuning through the night. Actually I broke a string in Guernsey the other day - first time ever since I stopped playing in rock bands (when I did two or three a night) so I kept talking and put on a new string pulling like crazy all the time. It did behave itself, but I had to use the 'pre-de-tune method:'

In this, when changing the tuning on a guitar mid gig, you have to slightly overdo the tuning - so dropping from E to D, you go just below the D. The string will relax slightly over the next minute or so (according to age, temperature etc), and settle where you want it. So the opening verse will be out, but the bulk of the song will be ok.

The general rule is never to retune a string more than one tone in any five minutes (IE per song). My sets were designed so I never had to tune more than one string one tone up or down between songs - and ideally I would detune at the end of the guitar song, put down the guitar, plays something else for a bit, and only then fine tune and play the guitar in the new tuning.

This is where a lot of folkies fall over (no names). In and out of DADGAD, Modals, STD, Dropped Ds - and no wonder the poor thing struggles to cope.

So here's a protip for the OP. Never go from C modal to standard in one hit. Go to DADGAD or whatever and play a few songs before you move on to STD. The strings should not break unless they are really old.

As for the sound - I don't like the very new jangle myself. I EQ it out on my on-stage mixer if doing a plugged in gig, or otherwise rub the strings with the palm of my hand to dull the tone slightly. On mandos a duller tone is definitely nicer - I know one well-known performer who puts his used guitar strings on his mandola, and I can see why.

I do like the response of new strings though - and the ability to get the tuning just so - which gets harder and harder the older the strings are.

Once again a plug for Newtones / Eaglenewtones seems appropriate.

Tom