It’s definitely possible. But as most questions like these, it really depends on the amount of objects, the size of your app etc. it does take some thought on how you’re going to manage client performance if there are just too many objects. If you’re going this route, make sure to test with actual production like data so you can check your apps performance.
Sometimes a mix of both persistent and non persistent entities would be a more favourable option.
Yes, it is possible, but as Larn said, you better do some test on the performance. You should also better first decide on the graphs and the charts you want to have and test them out. If I remember properly, there are several widgets that do not support non persistent objects (e.g. the Google Gantt Chart)