How much should Kingdom Elemental cost:
I'd say this game as is should sell for between $15 and $20.
15 dollars is a useless pricepoint, and that's been generally shown again and again on the indiegamer forums. I haven't heard anyone say that they increased their units moved with 15 over 20. Go with 20.
Game core: $20( $19.95 USD)
>>Expansion packs: $15<<