Craigkiller, the trick to 29 is luck, there is no way to say it nicely. Sometimes the triangles will slide, sometimes they won't. Generally, the start is 1 flat onto it the next leaning, then build from there.
This game needs group summoning... just basically instead of getting a castle upgrade should increase the number of units summoned per click, without increasing mana cost. ( some don't get any increases, just the lower level summons.)