Couple of things.
1. Bard is a 3/4 BAB class. So drop your BAB by 1 by splashing Bard. Of course, you've got DP, so that's not as big a deal, but something to consider.
2. Now you're committing to CHA; it is a mistake, IMHO, and you will regret it later. You can do it effectively, but this isn't the build goals.
3. UMD is very nice -- I have UMD on my Barbarian, so I know the addiction. BUT! As a cleric, consider carefully what you will want to UMD. Not Rez/Heal scrolls; you already have that. Arcane wands all basically suck, especially compared to what you can dish out as a cleric. Greater Hero? Teleport? Dim Door? These are all useful, but they are utility for utility builds.
4. True Neutral is great... but levelling up is harder as you can't use Pure Good weapons until 20 UMD.
Overall, I think you're trying to get too many goodies without prioritization. Prioritize then see how you want to approach things.
/gren