The main fix: performance has been improved.

Aesthetics:

• New selection effects: rings for mines and the main base, and rune circles for units.
• An animated construction grid and updated placement markers, with visual feedback for valid and invalid positions.
• Reworked territory visuals with smooth outlines, animated shading and flowing highlights.
• Refreshed lighting, sky, terrain, trees, glass and particle effects.
• Fixed mine panels and unit upgrade/sell controls appearing behind selection effects.