Is it necessary to use a whole variety of meditation techniques? I have been practicing samatha, vipassana and metta meditations for over a year.

I came frequently across articles (and questions on this site, primarly this one) describing other types of meditation, which can be rather confusing, because it is not often very clear what differenciate one from another, nor what is their purpose. 

Should I worry about all the other meditation techniques out there ? How far should one expect to go by practicing only a combination of samatha, vipassana and metta ?
I found experimentation helpful before I realised that some meditations require some form of mental application or you could refer to it as volitional noise. This, as I learned, became averse to me and so my practice is meditating while 'not doing'. This means I am just simply an observer of bodily phenomenon. It goes much deeper than this as one can observe with a kind of gentle organic intuitive processing which is helpful when seeing the threes marks of existence within the skandhas. Many people have given this meditation different names but I don't concern myself with that. Find your own comfortable technique but use Buddha's guidance as a framework. Here's a beautiful quote from the Diamond Sutra that illustrates this message.


  Awakening does not come from a set method of teachings but an internally intuitive process which is spontaneous and part of one's own inner nature.


Here's an audio version of the Diamond Sutra...

https://youtu.be/HK9u7Jz-vNA