If you are running dungeons mostly and plan on tanking as well you need Consecration. For healing Spiritual Focus, Illumination and Divine Favor are really nice. So I'd say that 21 points in Holy are mandatory if you are focusing on group play and support. I would move the 5 points from Divine Strength to Spiritual Focus. Together with Concentration Aura that gives you a 100% pushback resistance when healing. This is super useful in any case.
So I'd go at least with this:
21/0/0
With having the basics for tanking and healing covered you have a few options now.
If you don't care much about your killspeed when you are questing or grinding alone, because you run dungeons most of the time anyway, you could aim for Holy Shock. It is really useful when tanking low level instances actually. It causes a lot of threat especially when you let it crit with Divine Favor. So you can range pull with it and use it as a taunt. It makes tanking very easy. Most aim for 31 points in protection for tanking to get Holy Shield. But I think that build does not shine as long as you dont have Consecration as well, which would require level 51. I found just picking Holy Shock instead is making tanking way more comfortable before you are able to get both Consecration and Holy Shield.
31/0/0 You can move the points in Imp. Lay on Hands, Imp. Blessing of Wisdom and Lasting Judgement however you like altough the reduced CD of LoH and the armor bonus are really useful. Having that powerful ability every 40 mins instead each hour does make a noticable difference especially when running dungeons a lot.
From there you could either go for Protection to increase your support abilities (Guardians Favor) and threat (Imp. Righteous Fury) or Retribution to increase the killspeed when you are playing alone.
31/13/0 or
31/0/13
I usually went with the latter one. My build has been
31/0/20 most of the time with retribution talents that aid me while I am alone. Imp. Retribution Aura is better than Sanctity Aura for damage as long as you get hit. So if you are not doing dungeons as damage dealer/support always get that one if you have points in retribution. And it increases your threat when tanking as well. I tanked and healed every instance up to UBRS with that build. The only thing I am missing here is the +3% hit from Precision. Especially when using slow 2H weapons you will notice a difference.
You can also go for a support spec that focuses on protection talents like
20/31/0 or one that is focusing on Retribution like
21/0/30. You will notice here that I picked both Imp. Retribution Aura and Sanctity Aura with this build. That seems like a waste at first but if you don't have that much AP and Meleecrit Imp. Retribution Aura outperforms Sanctity Aura as long as you get hit. If your role is damage dealer/support in a dungeon group you can switch to Sanctity Aura to increase your damage output. Although sometimes tanks demand either resistance auras or Retribution Aura as it increases their threat.
The build your friend gave you looks good too basically. But I think the 10 points in Divine Strength and Imp. Seal of Righteousness are wasted as you could use them to go further down either the holy or protection tree to get the 31 point add some weight to a specific playstyle.
You see there are many ways you could go. You are lucky though. The cost to unlearn your talents is capped at 5 gold. So why not try all of them
If you feel you need to take a break from dungeons and want to farm/quest/grind a little give this one a try. It's a selfish spec but in my opinion there is nothing better for solo PvE than
0/26/25