I like giving this deck code out because I had so much fun with it in the past, and with the mindgates, it can be a completely different game every time.
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568 568 6qq 6qq 6qq 6qq 6qq 6qq 6qq 6qq 6qq 6qq 6qq 6qq 6qq 6qq 6qq 6qq 6qq 6qq 6qq 6qq 6qq 6qq 6qq 6ug 6ug 71b 749 749 74b 74b 77f 77f 77i 77i 77i 7gp 7gp 7h2 7h2 7k6 7k6 7k6 7k6 7n3 7n3 7q5 7q5 7q5 7q5 7q5 7q5 7t9 80a 80a 80h 80h 80j 80j 8ps
It can probably be optimized for effectiveness, but it's really fun to play. It suffers primarily to fast rushes, but does quite well otherwise. The idea was that I tried to make a deck that could (potentially) deal with anything, assuming it draws the right cards. Against the arena, I use a couple purifies due to the prevalence of poison. (this deck has no trouble with SoSa; it can just wait it out) I used to use it a lot against FGs, but with some of the AI improvements (yes, it used to be dumber!) it doesn't do as well as it used to. If you lack the nymphs, I'd use more CC or purifies, or possibly a miracle.
Adapting to your deck, I think I'd add pulverizer and mindgate to yours, and try to squeeze in a bit more creature removal. Also, I personally like steam machine more than forest spectre or lava destroyer in a slower deck like this, because in the long run it gets bigger, and 15hp is -really- hard to deal with. Plus, it's hilarious watching the AI do something like siphon life it six times and it's still alive... then you quint it :p