If they don't design a way for the content to last longer I can't see how they could spread them out more. What we need is more content that lasts longer like in vanilla, tbc, wotlk and actually to an extent cata.
Yes definitely.
We just started Highmaul mythic when BRF came out. Then we focused on BRF because ilvl drops is better and did not even step into Highmaul again.
If they decided to set same ilvl gear drop between those two raids, Highmaul would still be relevant after BRF came out.
Personally I think it should have gone Highmaul and foundry together, a brief smaller raid mid tier to upgrade that horrible Highmaul loot you might still have and therefore boost you through foundry and dungeons for catchup dropping equivalent to Highmaul normal gear then tanaan, then release HFC for the last 10months