Don't forget Magic Vestment. If you have Abjuration foci, you could potentially raise the enchantment on your shield to +18 or +19.
Magic Vestment would only offer +18 to this build progression, assuming you had legendary spell focus Abjuration (not currently listed in the build). Considering that doesn't stack with Girding* it's not particularly useful.
*Assuming you use the +16 illithid or rona tower shields, which are +18 with girding - the same as Magic Vestment would give with LSF Abjuration. I suppose the exception would be if you wanted to use one of the +13 tower shields and still have maximum AC doing so. I'm not sure which feats you could drop to get LSF Abjuration though.
Johann is right that there is a very nice hells set plate for Clerics, but there is also a very nice set of robes (in Maladomini, Pristine Way). So I don't think that matters much.
In regards to AC, I was thinking of a build such as Mish's, which takes Craft Armor and LSA: Tumble. With it, you can get your Cleric's AC to 130+ without too much difficulty. So there are a number of times that I would take 133'ish AC (I think Mish's was 136 after double-demi) over 115 in plate/shield, etc. The plate/shield requires a much better gear setup, because you just count on being hit a lot. So you need to cover immunities more, are more reliant on shunt, and need a specific gear setup. With 133'ish AC, you won't be hit nearly as often, and have a little more flexibility with gear.
But since this build isn't geared towards AC, I would agree that perhaps it's not a great loss to think about going Bard over Monk. With this build, though, as Johann alluded to, you'd have to find 2 more INT somewhere, likely at the loss of 1 DC to your spells, in order to make room for UMD. Or change subraces, at which point, as bort said, you'd have to change the build name.
Perhaps Svirfneblin would be a good choice though.
"Svirfneblin" - FC: Cleric - base SR0 +1/lvl, CON -2, CHA -2, DEX +2, WIS +2, free feat: Darkvision, saves +2, listen +2, hide +2, speaks Undercommon, speaks Svirfneblin It would mean no tower shield, but you could still use large ones (which generally provide better immunities throughout the mod anyway), you get +2 Wis, and you get +2 skillpoints/level (at level 41), which nets you 60 extra skill points over this human subrace build I think (no -2 INT, but losing the 1 skill point/level from Human base). You do lose 2 con, but that's evened out by Gnome base. You lose 1 to saves, from the -2 Charisma, but that's probably ok, as Fort would still end at 60, Reflex would still be poor, and Will would still be high. You also wouldn't have that 20% xp penalty, and some built-in Spell Resistance. Anyway, just something to consider.
As for the shield AC from Magic Vestment bort, I generally prefer a shield with 25% to two immunities, such as Demondim or Valiant's Honor, over 100% electrical immunity. So if you can have the same AC in either, I'd prefer the large shields. Once you get one of the two BUR immunity shields, it becomes even more distinct, getting 50% and 50/- resist to two elements.
Something else worth considering: The 'Slag' tower shield is (according to it's description) immune to Slag effects. Having Legendary Spell Focus Abjuration to boost the AC on it, plus being able to offer +75% immunity to the element of your choice seems like a very attractive option - at least for those who don't have a Ruby Rod lying around or aren't yet demi.
On second thought the shield is probably too heavy for anything other than a STR build, and it won't stop your armor getting slagged anyway...