Valkyries need the "Hog Rider" treatment
As of right now, one of the most useless troops in the game is arguably the Valkyrie. While she has a lot of health and does a ton of damage to go along with her speed, she costs far too much and takes too long to train. This was the same with the hog riders before the August 27th update (2013) when their training time was reduced from 5 minutes to the current 2 minutes. Also, the hog riders were given their preferred targeting of defenses, finally making them a viable troop and are now used in the popular Hog + Healing attack strategy.
The 15 minutes to make a Valkyrie coupled with her 70/100/130/160 dark cost makes her too expensive of a troop when other cheaper unit combos can do the exact same job (barbs + wizzies). If her training time could be reduced down to 8 minutes (like the balloons and wizards in the update earlier this year) and possibly have her costs adjusted to 50/75/100/125 (or something similar...maybe slightly higher), we could see this troop be used more in attack and defense strategies.