The Triangle is a visual way to represent how your character is meant to operate in combat. The three basic tenets being ranged, melee, and magic.
And that, as well, is completely acceptable. Ideally, a Warrior's triangle SHOULD look a lot like that. A Mage's triangle should not. That would mean they are putting all their capabilities into melee, which doesn't make sense for a spellcaster. The mage's triangle should look like a line going the other way, with "magic" instead.
The Hybrid classes (MRPG Paladin and MRPG Battling Sorcerer) get a bit more interesting. These classes are designed to have a certain amount of generalization. They are the bridge between the sword and the spell, and magic and combat become one. And because of course no self-respecting Paladin is going to let a little thing like distance get in the way, it helps to have some ranged ability.
Hybrid triangles can also look a bit more like this:
However, a good hybrid character should never be focused on a single skill to the exclusion of all others. What would be the point of taking the class otherwise?