I don't get it. Strava is a great product and is getting better. Training log, segments, the new route feature - no other service is comparable. So if you love it, why not pay for it?
Also, pretty much all the features that will be subscription-only are "really nice to have" but not essential features. You can still see your and your friends' runs. You will still appear in segments if you run fast (you will just be able to see the top 10 only).
I'd much rather pay for a great service that have ads all over or have Strava sell my data to goverments for $$.