Some thoughts based also on Rotoworld stats...

MARQUESE CHRISS (PF/C) - He is a full-on hybrid PF/C. He played 49% of his minutes at center, without Chandler or Len next to him...
ALLEN CRABBE (SG/SF)- He’ll be coming off the bench with a ton of minutes at the two and three.
JAMYCHAL GREEN (PF/C) - He saw about five minutes at the five and even three minutes at the three.
WILSON CHANDLER (SG/SF/PF) - Last year, Chandler was expected to play a lot of four, and they did go that route again in the preseason. Coach Mike Malone wants to go small in the non-Jurkic minutes.
TIM FRAZIER (PG/SG) - Locked in for big minutes even with other PGs at the same time and should have a
really nice dime rate.Classic combo guard.
MICHAEL KIDD-GILCHRIST (SF/PF) - He actually got a decent amount of run at PF.
D'ANGELO RUSSELL (PG/SG) - plays a lot of minutes off the ball in Lakers with Lou Williams and Clarkson on the roster...As these two players have PG eligibility also Russell must have SG eligibility...! 3 familiar style players...
MARCUS SMART (PG/SG) - He played over 800 minutes last year with Isaiah Thomas according to basketball reference, which is almost half of his minutes!

Playoffs are only eligible for 8 teams at maximum. So, I recommend to have an option for our Dynasty League w/ 18 teams as below format if it is possible:

12 team playoff (first 4 team have automatic bye & between 5th and 12th positions play against each other) - Taking place during Week 19 or 20

Between 13th and 16th position play consolation during that week.

In the next week first 4 team will match with the qualifying teams from the matchups btw 5th and 12th spots.

[5-12]
[6-11]
[7-10]
[8-9]

I think this addition will enable more teams to stay in Fantasy Game and follow the league as long as possible.

By giving the commissioners the ability to change position eligibility, changes in each league will occur much quicker and be custom to each league. For example, Steph Curry is always placed as a PG/SG, when people in my league agree he should just be a PG. Conversely there are guards out there like Lillard, Lowry, Westbrook, Ty Lawson and many more that have never been given SG eligibility when in fact they have played as SG. Additionally there should be a system that if a manager believes a position eligibly change is needed (ex. taking PF away or adding PF to a player), a request can be sent where the commissioner can review their proposal. Yahoo! can still roll out its own position changes, this just gives leagues more customizability and freedom. We hope this change is implemented soon. Please up vote.

Like the 1st ranked suggestion here, i am vouching for an update and a few alterations on player position eligibilities. I contacted Yahoo customer service via e-mail about my concern on this issue, i do not want to reiterate all the points i made so i will just copy paste my conversation.

I just personally think that having more position flexibility for certain players that make sense would make fantasy basketball even funner and more competitive. I understand that, for example, Deandre Jordan can only be listed as a Center because that is the only position he is capable of playing. But if another starting center like Myles Turner is capable of playing both Power Forward and Center spots he should be eligible for both (which he currently is), even though Myles Turner has started every single game this season at Center only. I just think that as long as a player is capable of playing two positions, he should be eligible for that position in Yahoo Fantasy Sports. It will help make the game more fair and competitive by allowing people like myself to be able to start active players and not be forced to leave them on the bench with an open roster spot because of a position eligibility, thus resulting in a loss of stats from persons who i could not plug into my lineup. All i am asking for is consistency. You said that "If the position change is considered temporary or situational, position eligibility won't be adjusted." Then how come Austin Rivers is PG/SG/SF eligible when he has only played a handful of games at SF only due to the recent injury of Chris Paul. Or why is James Harden also PG/SG/SF eligible if he has rarely ever played the SF position all season. I hope your data provider can seriously consider my plea as it would only enhance the Yahoo Fantasy experience.