Similarly what others have said, put the majority of tier 2 into Devotion and Shellra 5, if you want, 1 in martyr and Protectra 5.
As for tier 1, its a but more based on the person.
Your main useful choices however are Barspells, Regen and Cure cast times.
I personally have a Mix of the 3, but im also not dome meriting yet.
My main 2 im focusing on however are Regen and Barspell. Each Regen Merit tacks on 20 Hp to each Regen. If you use regens often, this is wonderful. Pair this with Clerics Briault which also boosts Regens and you can gave some very Efficient Healing over time.
Regen 1 is 5 Hp a tick, 2 is 12, 3 is 20. With Clerics Briault regen 1 is 6, 2 is 14 and 3 is 23. Not Put 4 merits into Regen and you have Regen 1 of 10 Hp a tick, regen 2 at 18 and regen 3 at 27.
Now add on Scholar sub for the 10% spell cost reduction and these spells get Very efficient.
Barspells are similarly important. Much more important if you do events then if you are just meriting however.
For things like Dynamis or Nyzul Isle, a potent barspell can halp you resist some effects. Like if you pair Baraera and Barsilencera with Whm AF2 Legs and a few barspell merits, you can have a barspell potancy of about 120 (and thats not factoring in enh skill +) I have had several Silences resisted like this. Or similarly barstonra and Barpetra and ive resisted Breakga 4 times in a row.
Since Cure casttime is in Tiers, you need to somewhat know how close to the next tier you are for them to make a difference. Also having Cure Clogs helps a lot with this, since they are a 15% cast time down. I don't know the exact cutoffs, but if i remember right it comes down to 1 merit will not make a difference, you'd need to do 2 before you see anything, again, im not sure, but im just useing this as an example.
As bar as banish effect, sadly while its amazing on the undead, you'll rarely make any real use for it.
Divine Seal recast is not Bad, but at only 20 seconds a Merit, there are better things to put merits into.
Again, these are just my opinions, read what everyone has to say and decide from there. Ultimatly, it will be up to you, and your playstyle. And you can also take some away and play around with them, they are not perminent, which is nice.
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