I find the card that is best for my purchases - for me SPG amex (starwod hotels) and Chase United Explorer. But for someone who doesnt want points for free flights on UA and free stays at westin/sheraton/etc hotels, its not a good choice.

I address the credit issue (large percent of available credit used by a large purchase) by paying during the billing cycle. For example, on July 1st I book a $4500 flight on a card due July 31st, I pay off the $4500 before the bill, like on July 2nd so my card doesnt show it as using my available credit for the $4500 when the bill is sent on July 31.