Halfling is a good-aligned race that can fast attack, explore, and convert. If you want to protect your platinum, Halfling is a prime choice due to their DP elite counting as a partial spy (1/3 when defending ops from other dominions, 1/5 when doing ops on others) - of course, this also means that you can lose DP when you fail spy operations on another dominion. In addition to protecting your platinum, it is very hard for other players to get spy ops on you, but you should not assume that this protect you from being underdefended.