My first thought was Block so that he is much more resiliant to the inevitable 1/2D blocks come raining in on him when one of his cage mates Boneheads and lets the opposition straight through.
Im also wondering about dodge though as this gives him pretty much equal* ability to stay upright and combines well with break tackle to make a very mobile ball carrier and much harder to pin down.
Last of the major contenders in my mind is Pro. The team only has 2 RR's and these are frequently burnt up by turn 3-4 since there is a lack of basic skills and critical bonehead failures mean they use many more RR's than the average team. Pro would drasticly cut the number of times my cage is stalled because my ball carrier can't move and is also a big help with Blocks, Dodges and GFI's al of which this player does in abundance mostly without a RR to hand.
Also pass might be good since he often gets bogged down and the option to make a quick pass to a snotling with catch is tempting. With strong arm as his next pick (a ST skill in the vault) he could be a reasonable passer plus it can be used to improve my TTM relyability. My main reason for liking pass though is that I've always wanted to make an Ogre player who thinks he's a thrower just like other teams have and if you put the ball arm on the throwers body instead of the goblin arm it makes one serously cool mini. However tracking down the right parts for this now GW dont sell them separatly could be a nightmare
.Leader could be really useful since as I said I never have enough RR's and at 140k a piece it will take me some time to get more through winnings. This is my least favourite option because this guy has the potential to be a real starplayer and Leader is not as useful to him personally as some of the other options.
*Yeah, I know tackle cancels Dodge but wrestle will bring down Block so neither is 100% effective defence, though I have seen many more tacklers than Wrestlers which gives Block a small advantage in the survival sence.
! To me it's a toss-up between Block and Dodge. I think that I would choose Block as it protects him as good as Dodge when he's being blocked but with the added benefit that he'll be much more reliable when he's doing the blocking himself (and he will also do more damage). 
! In fact, I was thinking of the same starting line-up that you have posted. But since the fixed starting-FF of 5 is now only an optional rule I might have to reconsider... (depending on which optional rules we are going to use in our league). Maybe 3 Ogres, 8 Snotlings, 5 Rerolls 
).
).
. You certainly need the extra cash and RR's you get from higher FF but it doesnt play anything like such a big role as it did in LRB4 and I wouldnt want to start with less than 12 players or less than 4 Ogres. If you win your games your FF should go up quite quickly, but thats quite an iffy stratergy with these guys so I dont know what's best to advise.
