Is there really a problem with 300+ post D1s aside from the fact it's a pain to read? D1 is almost inevitably always the "longest" day anyway, both in part because it has the full player list on hand and that it takes quite a bit of content to establish the general pace of the game and how everyone has chosen to go about things in that particular game (I frequently play with different tones and playstyles, for instance, but it takes time to make it obvious how I've decided to play).
D1 is a good establishing point, and it's probable that there will be A LOT of of additional content in choosing the first lynch anyway, as most times it is messy business trying to root out the scummiest player of the lot (and every other day will be established on the following deaths as well, cutting out a bit more chaos)
I think it's ridiculous to try and curb the post count D1 anyway, since it can screw over late arrivals, and shorter D1s just make it more hectic, and can even make the post count even higher.