1. Make lighting a "hybrid", something between mask and evaluated from field of vision, so behind the wall/floor it will be about 1/2 (discussable) of darkness.
2. Add "Abort" action while unit is walking (esc/RMB), if you change your mind or just missclicked. It is annoying especially because current pathfinder may route to anywhere you point, unlike originals, which failed to walk somewhere with complex trajectory.
3. XCom unit should receive shadow while travelling. Now he/she/it doesn't, like he's been illuminated. In original UFO xcom units were shadowed while they travelling into darkness.
4. Walking units still look strange (possible because of hands) - it should be examined further.
5. Mouse cursor should stay on screen while unit is walking (as in original). But in original mouse move while walking didn't affect on scren scroll (view area changed instantly when unit went beyond screen border). So either replicate original or make battlefield scrollable while unit walks. If so, maybe implement "combined travelling" when you don't have to wait until unit finish his move, and just select another and go somewhere else.