The first cheapest ticket you are shown is usually not the one you buy: the price is stale, the "direct" turns out to be two tickets, this seller charges more. We show the whole field at once and say which of it to trust.
Every pair of dates in the window side by side; filters apply instantly, without a new search.
Every price shows its age and its seller: the same seats differ by up to 13% between sellers.
Separate tickets are called separate tickets. About baggage we say only what we know.