In my opinion, there isn't much to mix when using Samples and VSTi. The vocal sounds nice and clear. Not a lot of character but valid approach.
The lofi strings sound too fake and off pitch for me. The piano could take more stereo space but those are artistic choices I can respect.
So if you want us to evaluate your mixing skills, try to mix a full band recorded with mics starting with the raw tracks.
There is some free to download stems outthere.
I'll be glad to help if you want to experiment in that direction.