Enormous orders can be cumbersome for customers--especially where tickets are involved. Until we reach that day when the print-at-home, PDF in an email of tickets is no longer a thing, 454 tickets in a single order is just asking for trouble.
However, other types of products are less cumbersome. As long as your sales channel maxes allow it, we've increased the max per order for all non-tickets to 50. Tickets remain at that 25-per-showtime limit, pending further review.