Tactics for Conflux.

a very decent option is to build 1-6 in the city — as they say, cheap and cheerful; buying at 121, and with proper battle skill, we can break almost anything we want :)

what kind of skill are we talking about :) , if with such an army you can't take even a 3-4 Griffin Conservatory or a maximum Hive, nor a Naga Bank at 6 ...
Even a near-maximum Hive, Naga Banks at 3-4 nagas will be a very big problem, after which it won't be possible to repeat the feat.
You can, of course, break Dwarven Vaults and Crypts ... or a level 1 Griffin Conservatory — but that's far from what you should be aiming for in the 2nd week.