1- double: guard.
It is extremely useful to break through enemy lines, and increase your chances of scoring a touchdown, particularly when receiving a kickoff (in this situation, it can be very hard to break through an excellent defense with several tackle players, and/or well positioned chaos warriors or black orcs without having to do loads of risky dodges, unless you have a guard player to help you make 2db instead of 1dbs...).
Yes, leader could be useful, but to be frank, you will use guard in a given match more often...
And with TWO lineelves with guard, you can protect your ball carrier a lot more easily. Anyway, you can always save money to get yourself the reroll that 'leader' would have been due to replace...
2- 110k? That depends on your team.
Assuming you have started with the typical 1wd, 10 linemen, 2rr and 8 ff (and therefore I assume you now have 12 players, with 2wds...), then buy definitely a third reroll. That reroll makes a lot of difference with only two.
If you already have three rerolls, but the players described above, then you may consider getting a thrower or a catcher. A catcher may be a better bet as it is usually advisable to make all your linemen pass to spread the SPPs. The thrower can always catch up later on.
And if you do have 13 players or more, and those three rerolls, then, and only then, I would recommend buying a treeman.
A treeman is a fairly good player, yet if you play a good WE game, your team will rely on its mobility, and the treeman will often end up on his own, easily cornered by your opponents... Of course, I don't even mention the fact that your treeman may not turn up for the first half, i.e. if you have 11 or less player for a given game due to SI or deaths, you will find yourself in great need of players who do turn up.
Finally, not having block and not benefiting from team rerolls, your treeman will not be a safe player to block on the front line with, so he won't be a fully reliable player even he turns up. Of course, you might argue that you'd give leader to one of the linemen as a reroll useable for the treeman, but then the first thing your opponent will do is to target that lineman and injure him, so that you won't be able to use that leader reroll when you really need it. I guess you've now probably caught my drift: a treeman when your team is fairly young is just far too much hassle.
Only get him when you have at least 13 players and three (normal) rerolls, and still, personally, I prefer waiting to have 14 guys before buying one of those...
, (sorry Al if your reading this 
). To be honest my opponent had real bad luck when trying to block and all my one on one tackles came out in my favor. 
