I have tried to have a look at some things online with Google search but there isn't anything very useful at the moment.

I was wondering which classes I should go for to get some cross class abilities that I will be able to use with my healing. Low Arcanist at the moment hasn't given me anything good for my healing, I did take Virus though but Psyhick is the same as Cure I (so far Arcanist gets the better deal when they go CNJ ).

I saw a table (that wasn't very useful because they didn't tell me which colours represented which class) but I gathered from one of the abilities that can carry over for the THM that I can use on WHM. Is THM good to go for for a WHM? Just to get the cross class abilities I mean.

There are a lot of other classes but I don't know much about a lot of the other classes abilities and if they will be useful to my healing.