By the way,

Can you guys recommend some upgrades?

I've been riding my Swift about 10 years now, and am thinking of sinking some money into it.
I have a mostly stock Xootr swift with North Road handlebars, a Thudbuster, and detachable pedals.
I've noticed that my shifter seems to only work in the middle 4 gears (or it slips).

There's also a soft rubbing sound when I downstroke.

I'm not sure if I should splurge on a IGH or get a different shifter/derailleur setup?

Alternatively, I'm thinking of possibly returning the bike to stock and using it only for fairweather riding.
I'm tempted to get a non-folding bike for commuting.

Any suggestions?