Hey Duke, thank you! That's very kind.
I have been composing for a little more than a year, but have been involved in music for quite some time now.
So, regarding the VSTs, I have a few go-to instruments (by no means associated with any of these, my opinion is after testing a wide variety of libraries):
1. For orchestral stuff, I use the East West Quantum Leaps Symphonic Orchestra (EWQL). It is one of the oldest sampled orchestras, but still does wonderful things and holds pretty well to this day. Of course, you could also go for the newer VSTs from Spitfire and so forth, but they are a little bit more expensive. Sounds wonderful as well. Nothing can beat the harp sounds on the EWQLSO though :)
2. East West Composer Cloud - this is an online subscription (IIRC, ~15 dollars a month?). If you are serious about composing music, consider subscribing to it, you get access to tens of thousands of sample libraries, including ones with folk and ethnic instruments, orchestral instruments, percussion and so forth. EW Hollywood Orchestra comes with the subscription and sounds as good as EWQLSO (but a little bit more "modern") - you would not need to buy anything at all and you can cancel the monthly payments at anytime.
In regards to synths, there are quite a few that I prefer, but did not use any on that song.
If you are going to buy any of these, I strongly suggest waiting for their sales. These companies hold sales quite a few times during the year. This year for example, on Black Friday, there were some libraries from Spitfire that had a whooping 60% discount.
You should also check Spitfire Labs - it is a collection with truly remarkable samples that are free! The pianos sound lovely!
Hope that helps!