一方 seems to be used at the start of sentences whereas [ippoudewa] seems more used to separate two clauses.
This example is a bad one. What does 内政要素はなく mean?
No resource management element :-P Well, techinically it's "domestic affairs" but in terms of computer wargames the general English equivalent would be "resources management". It's the 'mining / building / training etc, etc.' bit.
I admit it's a nasty example - but you should have seen some of the others.