I would like to talk a little about Geoffrey from a different perspective: versatility.

I believe at this point in the game Geoffrey is one of the most versatile commanders in regard to his usage.

1) PvP (arena, Galaxy League, mining and colonizing):
This is the obvious usage and I won't insist much on it. The shield is great in keeping a fleet alive, while in combination with Acc'tan he is one of the most resilient commanders out there.

2) Wormhole events:
This is one aspect usually overlooked when considering Geoffrey. Before I had him there was no chance to finish wormhole events, but after I did the situation changed. I am now able to finish 2 out of 3 wormhole events, so in a sense he is paying for itself in there.
Even during the class specific events like the current rangers one, although he is not doing any damage, the shield he gives keeps the rest of the fleet alive enough time to make it worth using him instead of a 4th ranger.

3) Primus Invasion
Another overlooked aspect. In the Primus invasion most top players are using Alfred with Krill lt. now in order to hunt Primuses. What this means is that most of the time around 8-10 people will make a monopoly in killing most Primus fleets. Thus the rest of the players will be killing escorts most of the time. Goeffrey is an excelent escort killer, making it so that you could basically put a fleet with him in a node and kill escorts there all day long if you put him first to shoot.
End result ... free R6 nuclears enabled by Geoffrey alone.

4) Pandora
This is an obvious usage. As long as in Pandora the damage made to shields is not counted, Geoffrey makes it so that you loose little supplies when attacking, allowing for more battles, thus much more influence.

5) Chaos Quasar
This is the place where he makes things "easy mode". Basically all you need to do is fully equip Geoffrey with the best galactonites and gear. Leave the rest of the fleet naked only with engine core on (for speed) ... and enjoy a fast and stress free CQ.

As a conclusion all I can say is that at the moment Geoffrey is a very versatile tool for most situations. Although the fixed shield might be a concern if lvl110 is ever released, I do believe it is high enough to be useful even then.