So I managed to find time to watch Mai no Mahou at last. You were right, it's very good - reminded me a bit of a much more cheaply made, less madcap "My Neighbors the Yamadas". There's nothing about it that especially screams P.A.Works to me, but it is further evidence that Yoshihara is a name to keep an eye on.
Same director as Uchouten... The visual style is indeed quite a departure (just watched 2 minutes). It's obviously cheap, but then this is a commercially-sanctioned advertising, effectively. It does have that daytime-TV look, with a bit of Ghibli in the character designs.
So I watched this PA Works OVA called Mai no Mahou to Katei no Hi. It's a 30min edutainment piece exploring a snippet of an everyday life of a typical Japanese family and values of a Japanese family. It was pretty much as good as it can get (bloody brilliant). It was done in a naturalistic, genuine, understated way and the visual style is akin to one that is acceptable on daytime television (Sazae-San style etc) since it's totally devoid of moe.
I highly recommend you check it out and if you require, I can provide a link to you via PM (subbed version ofc) since it's not the easiest thing to find. You know ironicially, it might actualy be PA's best piece of work despite being an OVA