Old bike questions

Thanks Ridgeback.
It is nice. Trying to improve my other bike resulted in lots more weight which is ok to me, just slows acceleration. Yet such reminded me; if it ain't broken, don't fix it.
It's lovely, would also better fit my friend and he rides a lot more than I. I had thought of lean bar, 9 speed but she ain't broken. Past has had my friend who rides about 2 cassettes a year to my best knowledge lend a bike between down stages.
To me, she looks like she'll feel comfortable and easy to maintain. Loving life, hanging until spring /summer.

Sorted.. Indexes.. 7 speed.. Bought it. Keeping as is.. No easy conversion using my skills. Besides. Light as. Less breakable parts.
Recyclable frame if ever broken. Smooth as..
Pissing down with rain at the moment. Going riding on the hub gearbox bike.
Boredom

Because I like riding.
I have 5 new close ratio 9 speeds.
My other racer isn't that posture, makes a great winter dry bike on wider tyres and is useful if a mate rocks up and wants a ride.
Our spring/summer/early autumn roads are useful on thinner tyres and because of the location, the ride to work along the range face is pick a ratio and keep pedalling, if a puncture does occur, fix, shorten ride and run down the hill to work.
I can't be stuffed refitting so I'm hoping linear shifters would allow a wheel swap using a 9 speed.
Life's simple. Fixie routes plenty too. Smooth roads between 0 &5%. Usually tending towards 0-2to3%.
Yet winters cold, often dirty roads, heavy clothes, wider tyres.
Hoping, shifter will adapt. Any thoughts please?
Probabilities? Yes/No

With love..