I also like eleven as an optimum number of blood claws. My own list has eleven with three fists and a WGPL attached to them with another fist. I'm of the opinion that the pack leader is overkill, but I have him there for fluff reasons.
The thing about land raiders is that they are a gamble. They are not all or nothing when it comes to gaining a win, but they are close. When they are destroyed in route and your pack sits pinned like a lame duck you'll curse them and wonder why you have one in your list. When they safely deliver a pack of blood claws who jump out and inflict massive damage with their 40+ attacks you'll ask yourself how you ever won without them.