My suggestions

[nildivision]

Firstly some disclaimers: I'm a trackball user, meaning that I generally have more difficulty with precise pointing than a competent mouse user. I have a lot of experience using many different applications across several mediums, and my prescriptions are generally informed by the expectations I've built from that. I imagine that some of these concerns already have solutions in the works or that I may be missing certain things (which is a concern of its own) - this is just a brain dump from my experience with Graphite so far.

• Unit type (e.g. in, px) should be specified for shape dimensions - currently they just show as numbers. #2813
• Deleting a node at the end of a chain should default to deleting that node alone rather than the entire chain.
• Instead, a modifier key should allow applying an action to the chain consisting of prior or latter nodes - e.g. shift + backspace to delete the output chain, or shift + drag to move that chain.
• The dot icon for exposing node properties in the graph should be slightly larger and have a hover feature that makes the user interaction more clear. Showing the triangle icon on hover might communicate this better.
• Pivot points should be able to snap and be controlled with other nodes.
• The central transform gizmo should be larger - currently the different controls it is comprised of are fairly dense and demand precise pointing.
• Shapes should have additional gizmos for their dimensions instead of having to use scale handles. This is especially important when transform nodes aren't attached.
• Node inputs should allow wires to be dragged from them in order to connect things "backwards".
• For viewing purposes, a fill or stroke should be assumed when previewing a path that lacks one.
• E.g. for math nodes, .5 should be interpreted as 0.5 - currently it fails to execute and gives no explanation. This truncated syntax is familiar to shader programmers and saves space.
• The acceptable area for dropping wires onto a connection point should be more lenient - making it the size of the entire box for that parameter seems OK.
• Artboard dimensions should accept inputs somehow. Currently there doesn't seem to be a way to pass the required type of IVec2.
• There should be a more accessible way to view non-shape node outputs than the Log to Console node. Having it show in the spreadsheet or when hovering over the node or its output seem like viable options.
• Pinned nodes should be able to display their custom name. It can be difficult to tell them apart when there are many pinned at once.
• There should be a toggle on the round corners node to only apply to sharp corners, likely as default. Currently running a circle through this node will change its shape.
• Similar to other vector drawing apps, guides should be able to be dragged from the rulers. These will be especially useful in Graphite as they can serve as controls for node parameters.
• Selected nodes should have their input and output wires highlighted to make reading complex graphs easier.
• Where "No search results" shows for a fruitless node search, there should also be shortcut(s) provided to create a value node named as the search text.
• Dragging a wire to a node without exposed inputs should prompt a list of possible parameters to connect to as a shortcut. This should also appear after dragging a wire to an empty space and choosing a node of this type.
• A search feature should be available to track down nodes within complex graphs.