Granted, expanding storage should require less items, or those items be made easier to find on GTHQ.
I find it a tad ridiculous that you'll need (for example) 20 storage bars, locks and cameras to expand at higher levels, which takes up 60 space. And equally frustrating having to trawl through GTHQ for hours to find a few of them.
But at the same time, I don't see how it's such a big dealbreaker that some have made it out to be. Or bad enough to make them quit (following the regional update).
My storage is at 320 only, but I can cope. One has to juggle, and cannot have everything their way.
Want to have big ready inventories of war items? Sure. But that means you have to have less of the 12 new regional items. Just refresh building plans if one is needed and you don't have it. Want to stock up on regional items for building upgrades instead? Then you'll just need to cut down on war items, or have less regular items to fulfil deliveries.
It isn't easy, but it's not impossible either.