there has been a fair amount of discussion on this in other threads. the following is my opinion, not meant to disparage others who have a different viewpoint on using miles.

for me, I find that using bonus miles to upgrade trans-oceanic or intercontinental flights is preferable to using said miles for buying domestic tickets or hotel stays, etc.

I base this (there's room for disagreement here!) on what I would have to spend in $ for the item obtained and the divide that by the miles. on AA I've been able to upgrade $800 tickets with an additional cash outlay of $700 plus 50k miles in lieu of paying $8000 for discounted business class tickets. simple math reveals that these miles trade in for $0.13, which far exceeds what I'd be able to obtain in terms of domestic tickets or hotel stays in the general case.

I also hope to use miles for award tickets to places AA doesn't fly. as I can't upgrade coach tickets on those flights (or some portion thereof) I view it as worthwhile to use miles. A partner award from US to Australia in business class takes 125000 miles, whereas a round-trip from LAX to SYD on QF is currently $17k. These awards are admittedly hard to get but the redemption works out to $0.14. I'd gladly fork over that many miles to avoid paying $17k!

This is how I look at using miles. I hope it helps the OP and others.