Love is not a low post big, he could score in the post with the right matchup but he didn't live on the block. If Embiid is as good as everyone thinks he will live on the low block and you need to build around him with that in mind, he will be versatile but he's not going to be taking a ton of jumpshots from deep.
The Hornets have a ton of trouble scoring despite the fact they have a post presence and a scoring PG, you throw MCW on that team and they'd be considerably worse because he's an even worse shooter than Kemba. When you have a big man spacing is important, the Spurs went with scoring PGs over pass firsts PGs and passed on trading for Jason Kidd because of that reason.
Love posted up nearly a quarter of all his possessions last year and has been doing it for close to a third of them in Cleveland. For the past few years he's posted up more than he's done anything else. The fact that he's a rangy shooter tends to obscure that.
I'd agree that MCW isn't optimally complementary to Embiid's skillset in the long run but not to the point where they can't grow together on a non contender for a season or two.
When it comes to spacing for post up bigs, the range of other bigs and wings on the team has a much more pronounced effect on spacing that that of smaller guards. The Hornets have close to zero flexibility in that regard on top of having non-shooting guards so its no wonder they can't score.
The Sixers are working with less than nothing in that regards and even with Embiid healthy the shape of a team simply isn't there so this really ain't even worth even thinking about just yet. Those concerns should materialise and become of high import once the team knows what its trying to be and that won't be on the cards this year (or maybe even next year).
You've got it backwards with the Kidd trade. It fell through because of Joumana and the Nets signing Zo. RC and Pop pulled out all the stops in recruiting him and were disappointed that it fell through.