Is this possible to store Media items in some other Content tree node in place of Media Library?
Since everything in the content tree is, at its root, a basic item, then yes, you should be able to store media items wherever you want. A few things to consider thought:
- You need to be sure the insert options are set to cover all the possibilities you want to allow
- You need to ensure your indexes are pointing to wherever you're storing your media items...look how the default implementation is done and expand from there
There may be other considerations, but if you test it out thoroughly in development, you should be able to find them all.
Yes, you can create media folder anywhere in content tree and upload media item in that folder. But, it's depends upon your requirement, sitecore by default consider media library as standard location to manipulate media items. You will not get your custom media location if you click on browse option for any image field. It will by default fallback to media library location, if there is no source path define for specific field.