We can not say that which is more important, saying tactfully or direct toward. There are always a pros and cons on something. And it is different between people and there are times that we think we have to say tactfully or direct toward.
First, when we say tacfully, we say like this to don't make tham feel hurt because of what I had says to someone. But when told them tactfully there are some people who tell us 'what is your point of this?'. Than we have to tell them the truth directly enough we don't want them to be hurt. Than they will tell me that, 'Why didn't you just tell me at the first place?' and than we will be angry at each other.
But at the side of saying direct toward, we can tell them our opinion more clearly. So they will able to understand it all. But when we say something direct towards, we can give them a hurt feeling. And there will be some poeple who will keep that hurt feeling that I have given forever. And it won't deleted from their heart.
Like this there are always a positive sides and bad sides. So I think that we can't say which is more important, saying tactful or direct towards.