I think part of the OP's point is that most other event prize structures add on the final tier - not replace with something of arguably less value (if you still need some of the ships in question...or one). And he's right.
This is the only event I've had to look at what ship shards are given out on the lower tier and "decide" between other rewards and the shards. Most events just add rewards to the lower tiers.
This one is different - and hence, "doesn't make sense". At least given the structure of almost all other event prize structures.
