Thanks for all the really helpful comments and advice.
I have gone with Block for Plagric. I can see that this is the best way to start.
I have had a chance to look at what else happened during the game.
1. My fan factor went down from 5 to 4. This is going to make it difficult to benefit from the FAME modifier in the next few games, which could dampen the cash flows.
2. I didn't roll well at the end for financial reward. But still I had £60k to spend and so have invested in a new Lineman (£50k). As I have learned I am a bit squishy so this should help keep me at full strength for a time.
3. Both my Blitzers gained a casualty and therefore 2 - SPP's. This is a good steady start and puts them in a good place to maybe benefit from a skill after the next game. Their Blocking was very effective and I used them with the Linemen to do some chain blocking to really move around the opposition. I was lucky with some high doubles when rolling for Armour and Injury. Not complaining about this as it gets the Skaven off to a good team building start. I have been thinking Mighty Blow / Tackle for these guys but still more reading to do.
4. A second Gutter Runner scored a touchdown which gives him 3 SPP's. Again this means he has potential to skill up after the next game with potential to head in the Wrestle / Strip Ball direction.
5. Plagric actually gained 9 SPP's. An excellent start for him. I have given him Block as the skill upgrade but importantly he is well on his way towards the next potential skill at 15. If he does anything at all in game 2 and gets MVP (worth 5 SPP's) he will be there. Tackle is awaiting this outcome.
6. Finally - one of the Linemen also scored a casualty for 2 SPP's. I was thinking that if he could get to 5 SPP's I might give him Kick. This would mean a more accurate ball placement after kick off.
I have learned a lot in Game 1. The Skaven have a completely different 'feel' to the Orcs. I think that I will need another couple of games with them to really get into my stride. They are all about movement. The key seems to be to do what is necessary to achieve that movement and only at that stage do other stuff. Open holes, move through and then do other blocks / dodging / whatever.
The dice are your friends but can be fickle. Don't over use them and expect that they will go on forever. ;-)