I currently have 3 RTWs open, also the return of a CMB-LAX is still open. As soon as you start travelling with RTWs (especially A) you get addicted and likely can never stop....

- If you like to travel in First, then the Star RTWs with the LH program get you tons of miles (3 to 3.25 times actual).
- If you travel Business or Eco then the AA program after/with a Platinum challange gets you mos miles (2.5 times in Bus)
- If you maximize sectors etc a 6 cont OW RTW gets significantly more miles than the Star.
- If you run out of sectors and/or miles then buy tickes inside the continents locally. Good places for inexpensive fares are Australia and Bangkok.
- If you want to break up the trip: Good places for inexpensive Business or First tickets back to NorthAm are CMB (esp. to SFO and LAX) and BKK. Also TIP is a good place for Europe, better than CAI or IST.
- If you nest RTWs: good starting points are BKK, CMB, IST (see other discussions here)
- As soon as you have enough miles use miles to return home (typically around 100 K for a Business ticket, the LH program allows companion awards for Senators (100 miles per year, which you get from one long Star RTW in First) - second person is half the miles. From two Star RTWs in F you get enough miles for more than two trips back home.

Also do some search for the rules on this board. This answers most of the questions about stopovers, passing thru the same place more than once etc....
Have fun!