Yeah i would not change the whole campaign to broad at first, namely because doing phrase and exact match give you targeted customers which is what you want anyway. Going broad may get you more clicks, but if it's the wrong type of people who cares, you may be burning money. If you want to experiment go broad with a couple and see if your conversions get better. You may find it more effective to get more targeted keywords in another related niche group of people who would need your product to boost your profitability.