HylaRadio,

Here's the quick and easy primer on possible ways to upgrade into business class from coach:
1. Use miles. Note, however, that most airlines offer a very restrictive (=expensive) set of fares that you can upgrade from using miles. Often a discount business class ticket is not too much more expensive. Northwest/Delta is one of these airlines.

2. Use cash co-pay + miles. These airlines allow you to upgrade using miles from a wider range of fares, but you have to pay a cash surcharge along with the miles. The surcharge will be somewhere in the area of $300-400 per direction, so $600-800 per round trip. American Airlines is one of these airlines.

3. Earn elite status on an airline that gives out System-Wide Upgrades as an elite benefit. Various levels of elite status/benefits are usually given out based on how many miles you've flown in a year, typically 25,000, 50,000, and 100,000. Some of the airlines, usually at the higher levels, will give out system wide upgrades as one of the elite benefits. United is one of these airlines.

That being said, I would look at Eva (BR) and see what their ways to upgrade are like. If you can fly some flights in E+ and earn the miles/ability to upgrade on others, you'll be more comfortable all the time.