going for a very simple theme (dark and rounded)
this is the idea I have for the concept (I still need to fix the viewportframe size, and that the viewportframe is above the hotbar number)
but besides that does anyone have any suggestions on something I should change or add to the design?
I should mention that this is going to be for a building/survival type game
I like the design a lot right now, great job!
I think that something that could be cool to add is sounds for your menu, it can help add to your minimalist style, like a simple click or something similar.
Hope this helps!
Lolaphobia
Yeah, I’ll make sure to do that thanks
I like this minimal design.
I agree with @Lolaphobia. I think you should put an animation maybe a drop shadow to show that its selected, instead of using a square to show that its selected. Think this would be appropriate to do since it will complement the curved UI which you have going for all of your UI elements.
Also, in case you haven’t thought of, make sure to make more use of the UI constraint items such as UITableLayout and so on.
Yeah i’ll change the selection box and I’m using UI aspect ratio constraints to keep the squares square and also using UI Grid layouts and table layout for the hotbar
You should make the objects a bit smaller so the player can see the full object and so that it doesn’t go out of frame
Yeah I already referenced that in the OP
Look pretty good right now.
This looks great so far, nice work! Here are some of my suggestions:
I agree with @Lolaphobia. Sound effects would make this a lot of fun.
I really like the way the selection boxes 1, 2 and 3 resize to indicate the box you have selected. I would suggest applying this to the items in the Inventory box as well. It would be a nice effect to have the item boxes get slightly larger as your mouse hovers over them and it would also be a good indicator as to which item you are about to select.
Adding an additional hotbar box for key 0 would be a cool addition too.
At the end of the day, I don’t know what your vision for the game is but hopefully these suggestions are useful!
It’s a very good, simple theme. Only thing I would say you need is something signifying that is the inventory. Also, with the inventory, I don’t know if that’s just a concept or anything, but usually things fill left rather than center out. Just make sure to keep the grid gaps the same vertically and horizontally!
EDIT Just thought of something… Tooltips are always nice. Those are easy to make too by checking when the mouse enters a box.
Perhaps allow using the number keys to quickly assign a position for an item. Similar to Minecraft, where you hover over a spot in your inventory and press the corresponding number for the hotbar and they get swapped
Also, finally proper usage of Viewport Frames 
Love the minimal design.
Only suggestion I have is to make it a little less opaque? I think its just a bit too transparent personally, but that’s a very minor detail.
Love the design, keep up the great work!
Linking with above, make it this opaque when the menu is open, but when they close it, the toolbar should become slightly more transparent.