I have finally had a few moments to pull the guitar apart, do a proper cleaning and of everything and put it back with strings that haven't been rusting away for a few years.
it still sustains like a beast, but it's a bigger adjustment from my 21-fret MIM strat than I thought, the neck is a little wider too. It does play rather nicely though. One thing:
The tone pots:
Everything happens between 1-3 and Nothing happens between 3-10. I checked they are the right linear pots. Can this be the cap? It's some brown thing not the green that is in my MIM strat. The volume was changed from a linear to an audio taper - but honestly, I think I prefer the linear. With the audio taper it seems more difficult for me to get the right drive/clean adjustment, here again most of the change is between 7-10 and not a whole lot at 1-7.
Can someone maybe suggest something here?
Maybe I am just used to my MIM's strat's controls because it is a little unconventional (500k instead of 250k pots) and it also has a different configuration (no tone on bridge pickup, bottom tone control is for middle pickup only). I just find it nicer/easier to find different tones I like. Should I just change this new one to match that or rather put in time on this guitar and see if it grows on me? Also, what was the original configuration - would anyone know? I think the pickups are still the original ones btw.
Other than that I for the first time ever managed to intonate my own guitar which I am rather proud of. Although, I have some buzzyness - it's either too-low nut, or truss rod fiddlery which I am not comfortable with to mess with myself so I will get it properly setup. The pins for the tremolo-bridge also needs to be replaced (one is badly bent, so if you adjust the bridge up/down it actually also moves forward/backwards/sideways).
Other than that, man it is pretty all cleaned up: