1 - Make mines easier to detect
2 - make mine harder to destroy/defuse
3 - prevent mines being planted in floors
4 - allow doors and windows to be mined
5 - mine clearing tanks
6 - mine detecting dogs
7 - Bangalore torpedo
8 - more mine types
9 - mines should leave a trace such as a pile of dirt or leaves
10 - a mine laying clearing class would be great for defenders and anti zerg charge paratroopers.
the idea is that a mine field should force a choice go around or accept loses time or blood, it should not be a surprise death. Imagine if artillery and bombing runs gave no warning before hitting it would be a nightmare.