you've started down this road of refitting a dear old bike, so it is what it is, but I still have my first touring bike and about 15 years ago thought of modernizing it, but realized for various reasons it wasnt worth it. I still fixed it up to an extent and still use it on a trainer, sentimental reasons keeping it really, but measure the rear frame area to see how wide tires you can put.
My bike is from about 1990 and both the fork rear area are limited to about 35mm tires. I had 32s on it with fenders at first, but ran 28s on it always afterwards.

I can measure the distance between the rear stays near the bottom bracket on my bike if you want, but measure yours in mm at widest point.
If you are happy with 32s I guess its a moot point.

what crankset will you use, the original?
So many options of setup, but it does come down to how much money you want to spend while living with the limitations and inherent design of a 84 frame.
My 1990 bike was always a bit flexy also, and that cannot be "modernized out" with new parts--but depends on how much weight you think you'll carry and your body weight.