Thanks for asking and looking forward to any feedback on oneworld from the members perspective. Here's a few comments from members regarding the Star Alliance, so you can see how they gave it a grade and what they said. Any format like this and many as well list bullet points for positive and negative aspects of the alliance or the program. Hope this helps and thanks for volunteering your comments.

Randy

EXAMPLES
Report Card
Grade: B+
The status benefits are excellent and respected throughout the network (with a few exceptions). Some places could do with more training on the benefits; e.g., LAX baggage handling seems to ignore priority tags.
However, the computers of the airlines and programs don’t seem integrated enough with ongoing issues of getting status recognized, and also posting of mileage to programs other than the airline flown.
. Some more clarity of lounge access would help, especially for those lounges that are contract lounges rather than airline-operated. The Star Gold access differs between contract and airline-operated lounges, which I don’t have a problem with, but it is not obvious in advance unless you know (e.g., through personal experience or research on FlyerTalk) which lounges are contract lounges.
. A number of programs offer more than one Star Gold status. It would be nice if a new tier was created for those high statuses with extra benefits (perhaps restricted to the airlines with the extra status) - currently the extra benefits are limited to one’s own airline..
Rob

Grade: B
Membership is pretty well spread throughout the world, with every continent having at least one, if not multiple members. Some member carriers are not up to par, however. Varig’s ongoing financial crisis means Star is underrepresented in South America. US Airways’ merger with America West may have saved the carrier, but the quality of the product is still sub-par. Although Air New Zealand, Singapore, Thai and United make getting to Australia easy, the demise of Ansett has been a blow to getting around Australia with the Star Alliance.
. Award availability is, of course, a byproduct of each individual airline’s program, but most Star Alliance airlines seem to be fairly good at working together to release award seats to each other as needed. As with award seats, mileage earning rules are unique to each carrier, but I think miles seem to post very quickly from other member airlines’ flights. Additionally, there’s not any situations I know of where some routes don’t generate miles on partners, such as is the case with American and British Airways on transatlantic routes.
Star Alliance elites are well-recognized by most member airlines, and access to lounges for Star Gold tier members traveling internationally is not only universal, but fairly well communicated.
. Star Alliance Round-the-World services are head and shoulders above what’s offered by oneworld, with better ticketing options, easier planning and fairly coordinated schedules.
.Richard Mendell