Something I've never understood is why people change things on their guitar.
When you bought it, it had a sound that made you say "This is the one". It's what made you buy it.
That's certainly a valid point of view.
In my case, when I bought my GC-5 I was discussing it with the shop owner from the beginning – I told him I liked it but the treble was a bit overbearing. I asked him if another set of strings could bring up the bass a bit. He said sure, try these D'Addarios (EXP PBs.) So based on that I bought the guitar, changed the strings, and was quite satisfied.
Later, after reading all the threads about different saddle materials on the AGF and UMGF, I decided to see what my GC-5 would sound like with a different saddle. I talked to Bob Colosi about it and decided to go with a bone saddle based on his recommendation. The saddle made a hair difference in the sound – again it appeared to me that the bass was a bit improved, which to my ears was a good thing – but the main difference was that the sustain and overtones were improved. More overtones but also more clarity. It was really lovely; the Taylor chime is still there but everything is balanced and clear. It was certainly a worthwhile change for me.
I also put a bone saddle in my Voyage-Air, which has laminated back and sides. Now, I bought that guitar because it folds, and not because I was completely sold on the sound. I'd tried the all-laminated model and it seemed a bit compressed. After reading reviews at the AGF I decided that the solid-top model was the one to get. So I bought a used one from another AGF member, and again tried a bone saddle from Bob Colosi. And that made an impressive difference to the sound of the guitar - it increased the sustain and overtones noticeably, and also gave the sound a rounder, fuller quality. It also helped the note differentiation.
So, my experience has been that a change in saddle is inexpensive and can improve an already-good guitar.
Changing strings and saddles is cheap, and it is a fun way to see how your guitar responds.