Zippy,
i agree with you wholeheartedly. we build a lot of 360's, 408's and bigger using everything from LA blocks, Magnum blocks, R-3 blocks etc. i have a customers car in the shop right now that sounds very similar to what you mentioned. it's a 66 dart with a 360, magnum based motor but with good parts and better heads that flow in the 280's. TTi headers, Schumacher conversion mounts, etc. it'll likely never see a drag strip and the plan is to make it a daily driver. one of the MP crates would've worked fine for that. the Gen 3 hemi would be even better with the abilty to get better fuel mileage, better cold starts etc. etc. etc. fuel injection is the way to go IMO whenever financially feasible.
you simply can't please everybody, but there is still a market for crate engines IMO.
we've been extremely busy so i've only built a handful of 360/ 408 magnum crate combo's over the last few months and they're relatively mild at only 475-525 HP (depending on the combo) but i've sold every single one of them in a short amount of time. cost wise, they are more expensive than the MP crates. they are not racing engines, so to speak but will serve street/strip duty quite nicely with the parts they come with.