Hi abhishek,
Am glad to hear that you have just been attuned to Reiki level 1 about 3 months ago. Instead of getting re-attuned to level 1, would you like to be attuned to Usui Level 2? To refine the energy, the best way is to practice using the energy daily. As you grow more accustomed to the energy, you will have a better sense and flow of energy!
There are different methods employed in attunement. The method Usui Sensei used is commonly known as the reiju method. The method that is commonly know today is Usui Shiki Ryoho (Western lineage of Takata). The more traditional method of Usui style is known as Usui Reiki Ryoho (Traditional style). I guess Takata had to adapt Reiki differently to the Western culture, as i believe at the time that Takata introduced Reiki, Eastern culture and philosophies was not very popular in the west as it is now.
The traditional method Usui employed required lots of meditation and training in order to move from 1 level to the next level. It may take up to 2 years of training before you can reach level 3. That is to refine and made sure that the students understand what they are doing before they move on.
However, in today's fast food culture, we may not have that luxury of time!! Or maybe we do

Takata formulated a way that can be reproduced by her 22 students (they were suppose to maintain the same systems), however, every one is an individual. They started to explore more, hence, the many modalities.
Even within the Traditional Usui Reiki Ryoho system, there are differences between Masters. Each having their own styles and methods. We cannot say one is better than the other!
Usui was the pioneer of the system, i believe his first students were test subjects for him to improve and better the method of passing on the energy! He may have given them weekly reiju to increase their sensitivity to energy usage! By the time it reached Mrs. Takata, they have gotten most of the foundation and fundamentals!
abhishek, i think you have a great idea to concentrate on Usui 1st, and then move on to other systems. As Usui is the foundation of most of the systems! However, if you feel you need to be re-attuned to Level 1 again you may do so....
Listen to your Heart 
To build a mighty skyscraper, we need to first create a firm foundation!!
Many blessings
xian