Let's just assume for the moment that forced movement does not count. How *can* Storm Pillar be used successfully? I know this is kind of a fork, but I think it's relevant and I'd like to see this thread become helpful to Stalker0, who has been so helpful to all of us.
I've spent some time drawing Storm Pillar on graph paper, and have found numerous cases where it can be very useful in controlling the battlefield. I don't want to mess with pictures in this post, so I'll just summarize the uses I came up with.
1. Completely blocking narrow cooridors or entrances such as doors that are only a single square wide.
2. Partially blocking wider doors and corridors and forcing opponents to take damage if they want to close. (Note that because of the restriction against moving diagonally around a corner, the opponent will have to enter at least two squares to get through, taking damage twice.)
3. Constricting larger areas so that opponents will funnel into a smaller area, thus concentrating them for area attacks by allies, and also making it easier to create a defensive line.
4. Splitting the opponents by delaying until a few of them have entered the "arena" and then placing the Storm Pillar behind them to block the rest.
5. Trapping a specific creature by readying an action for when it enters a
specific square (or squares) and then placing the storm pillar directly in front of it. This will only work if the creature has walked into a bottleneck, and would probably only be truly worthwhile if the creature was vulnerable to lightning damage.
6. Placing Storm Pillar directly in front of the party to keep minions from closing, or behind or beside the party to discourage flanking.
The worst cases would be: combats in an open field, where there are multiple ways for the opponents to avoid the area; opponents with strong ranged and/or area attacks, that have no need to close with the party; and opponents with lightning resistance.
I can readily see why non-human characters would avoid Storm Pillar, but when I make my next character I look forward to making her a Wizard with Storm Pillar in the starring role.