I am grinding IG now and getting a lot of good gear. But, I dont have room for it and I need silver to keep cracking shards. So, I am being forced to cull the new gear mercilessly. It almost hurts to hit the Sell button but it has to be done.
You can always mule some gear on your lower champions if you think you need to keep a bit more
I am putting lower quality gear on FW champs that I feel will be replaced over time. You have a good idea. I can store gear on some champs that I wont sell. Thats creative.