Here is something that I wish I had at the time I prepared my grant application: examples of successful grant applications. I remember spending a lot of time googling for advices on how to write a convincing proposal, and not finding anything but generic advices. People apparently don’t like sharing their proposals, which I can–partly–understand.
Now that my ERC project is over, I’ve decided to share my successful proposal. Don’t take it as an example to follow precisely, of course. All proposals and PIs are different, so you need of course to find other sources of feedback, but I hope it may help you prepare your own proposal and putting them in a good shape. Also, remember this was several years ago already, the calls have slightly evolved since then.
I uploaded the entire proposal on Figshare, you can find it here: https://figshare.com/articles/My_successful_ERC_Starting_Grant_Proposal/7110767
Let me know if you have any questions !