About curse : it only works if you can hit your opponent, so if basic spells are maxed out it no longer becomes a problem. Also Poison, Burning hill, Great Sea can easily counter it with repeated poison wave then poisoned death, burn & remove effects, absorb damage respectively.
I think the 'Practise' button in training is rather useless, it doesnt give any stats but take up same amount of time as actual training, it should atleast give 2practise/week