Here are some of my thoughts to seperate the two:
Barber
-In PPR leagues, he's a no brainer over Portis, because he will catch 20-30 more receptions.
-Familiarity with offense, Manning, Burress, and Shockey return
-Age, should we be worried about him turning 31? What about the retirement talk, is the fire gone?
I don't know if Tiki is a no brainer in PPR leagues. While you can put Tiki down for at least 50 receptions for sure, I also see Portis being more involved in the passing game with Al Saunders now running the Offense. One reason I'd kind of agree with you though is that Tiki had 38 of his 54 receptions in the 2nd half of last year. (He only had 7 after the first 5 games) Does that mean it took a little time for Eli to start connecting with Tiki, or just a fluke. If you think Tiki will haul in 65+ passes, he may be a no brainer in PPR. I actually have them pretty even in PPR.I do like the supporting cast, and think it will keep defenses from keying on Tiki.
His age does worry me, although he keeps himself in great shape. I just worry the coaches will want to keep him fresh by reducing his carries.
Portis
-Should get more carries which means more opportunites
-New Offensive system (OC)
-More weapons added on offense (ARE, Llyod)
Portis had 343 carries in 2004 and 352 in 2005, so I don't see his carries going up. But, I do see his goal line and redzone touches going up. Last year Wash used a lot of short passes near the goal line but this year with Saunders in town, those chances should go to Portis. While in KC Saunders fed the ball to the RB's at the goal line.I am not all that sure that adding Randle El and Lloyd will scare many defenses. Both are average WR's.
My only concerns with Portis are the QB position and L. Betts. If Brunell stinks or gets hurt, teams may key on Portis. If Portis doesn't get the job done on 3rd downs or at the goal line, they may call on Betts.
I currently have the #4 pick in a PPR league and have yet to decide on these two. I'm leaning towards Portis. It will be one of them for sure. I've owned Tiki in the past and know how good he can be, but I'm a big believer in the SYSTEM. Tiki is in a great system in NYG but if Al Saunders can do in Wash what he did in KC, Portis could be huge. Wash may not be KC, but their line is good and their WR's are actually better then KC's. They don't have a Gonzalez, but Cooley is a pretty good TE. Never owning Holmes or LJ, I know how p'd it made me watching those guys getting all the TD's under Saunders, I can see the same thing happening with Portis. It would sicken me if I passed on him when I had the chance to grad an Al Saunders RB.
I can easily see Portis putting up:
345/1600/14 (4.6 ypc)
40/375/1 (9.4 ypr)
40/1975/15 = 287.5 in non PPR & 327.5 in PPR
With a chance for more TD's and maybe a few more rec's.
I can see Tiki putting up:
320/1500/9 (4.69 ypc)
55/575/2 (10.45 ypr)
55/2075/11 = 273.5 in non PPR & 328.5 in PPR
With a chance for Fewer TD's, fewer carries but more receptions.