TTA Cherokee Driver wrote
So I've been thinking of buying a plane for the sole purpose of
improving my availability & flexibility.

Which is indeed the sole purpose. If you're in a club that's a good
deal, you won't come out ahead financially by owning.

Since this is a philosophical discussion, assume if I buy on my own I
will have to buy a VFR airplane to get a decent one that's affordable.

The difference between a VFR airplane and a minimal-IFR one is often
small, but OK.

If I buy a VFR airplane that would rule out getting an instrument rating
because I'm obviously not going to rent airplanes for over 40 hours of
IFR training if I just bought one.

Well, if your VFR airplane has a gyro panel and a VOR (and most do)
you could probably do most of your training in it, and just rent
something for about 10 hours. But what would you do with an
instrument rating owning a VFR-only airplane?

I'd like to hear people's thoughts on having the hypothetical choice of
getting an IFR rating while continuing to rent, versus buying and
committing to being VFR-only for the forseeable future.

I think an instrument rating for a renter pilot is a bad joke. Most
rentals are not maintained and equipped well enough to be reasonable
choices for flying IFR in most non-VFR weather. Most renter pilots
don't even fly enough to maintain VFR proficiency, never mind IFR
proficiency, and the problems you describe are part of the reason. To
me, this is a no-brainer. Buy the VFR airplane.

Realize that the number of times you will be able to complete the trip
in a typical club/rental airplane with the instrument rating when you
couldn't do it without will be fairly small - much smaller than the
number of times you will be able to complete the trip by adjusting the
schedule a bit with your own airplane when you can't do the same with
a rental/club airplane. You will fly a lot more as a VFR owner than
you will as an IFR renter.

Instrument ratings for pilots of light singles are WAY overrated.
Think back to all trips you cancelled because of weather. How many of
them could you have completed with an instrument rating? Not the ones
in winter, because now you're flying in clouds that are subfreezing
and can leave you with a load of ice any time with no way to get rid
of it, unless your club has a plane with boots or at least a big
engine. Not the ones where there are thunderstorms hiding in those
clouds, because you have no way of knowing where those storms are
unless your club has a plane with spherics. And if the clouds are
really low, how are you going to fare if that engine decides to quit?

There is a reason that the vast majority of instrument rated private
pilots don't stay instrument current - it's just not very useful.

Michael