First off, I'm a bit new...I've been playing for a few weeks and LOVE it.
However, one thing that I'm surprised I don't see talked about much (at least from the little time I've been here) is the stash size. While I'm glad it's significantly increased from vanilla D2, there's so many additional items added in Meridian, I don't believe the stash has been properly scaled to accommodate for the additions.
There's 240 blocks in the stash (16x15)
-There's 16 shrines (2 blocks each)
-12 Gems
-50 base runes
-13 high runes
-Mark of Infusion
-Catalyst of Learning
-Arcane Crystals
-Arcane Shards
-Depleted Riftstone/Charged Riftstones
-Belladonna Extracts
...and so much more. But I believe these are the basics of what most people would try to keep readily available at all times. Assuming you only kept 1 of each (which we know is unrealistic being you have to transmute runes/gems, thus you need 2 of each) that's 113 blocks - almost half of your stash! In addition, many items require multiple gems/runes of the same. Thus, this isn't a realistic rendition of how many runes/gems you'd keep on hand.
More realistically for me, I keep 1-2x of each rune type and transmute my 3rd find, so I can transmute it up, whilst keeping the base. That's virtually 163 blocks in use leaving a measly 77 blocks for storage. That still isn't counting jewels you may save for crafting gear, arcane shards/crystals, and any additional gems. This typically takes up another 15-25 blocks for me. Now I'm down to 50ish blocks for actual gear storage.
Mind you, it's not like I keep everything I find. I'm very particular about keeping my stash organized and cleaned and not hoarding junk. Yet, I find myself only being able to stash away 4-6 pieces of armor/weapons and a few rings/amulets.
I'm sure an argument would be not to store 2x runes of each, but keeping only 1 on hand doesn't make sense to me. Because when you find the 2nd and transmute it up, you lose the lower rune (yes, I know you can transmute down, but what if you need both?). I don't know, maybe I'm asking too much.
To make matters a bit more difficult, the cube for storage is useless in my opinion as crafting in this game is 24/7. You're always crafting something. Thus, it'd be a bit difficult to juggle storage between your cube, stash, and inventory when you want to transmute something.
...and inventory space is also limited considering there's 35+ trinkets for you character from ubers.
All-in-all, I'm hoping someone could shed light on this topic as to what their opinion is and/or if the devs are considering increasing the stash size.