Which one forms the best couple?

Compatibility between couple is because of many things , most importantly because of compromise on both sides.There never can be a perfect match , so we have to make the best of what we have got ! If there are at least a few similarities in interests it does help a lot ...

It is very rare to find two persons exactly of the same kind and to be very honest I believe that similarities can usually create a hassle in the relationship while dissimilarities may strengthen the bond. Suppose both are stubborn and egoist then no one will try to mend the gap created between them due to any misunderstanding but if one is less stubborn or not egoist then rift can be easily overcome. So, I prefer the couple must have a little bit of dissimilarities in their basic attributes but moral values should be same such as both should be honest because if one is dishonest then that relationship will not be a great one. 

Trust,patience,understanding and care is important for a good relationship.

Similarities or differences- if both like each other, they are good couple. The differences make them complementary to each other. So if one of them is simpleton, the othr one should be very smart.

Couples with some amount of similarities and few differences works best. For difference will lead the way for knowing different aspects of the same thing...and similarities will help couple to enjoy any activity that they both like. Works well for both.

Opposite poles attract. This is very much true in married life. If I'm an artist and my wife doesn't know anything about art, the curiosity to know about the unknown things will lead to a congenial atmosphere and paves the way for harmony. The same thing holds good, if my wife is a classical dancer and do not know about classical dancing. This makes me to interact with my wife to know the nuances of classical dancing. Interactions will open flood gates to understanding and harmony.
That's why, the best pair would be that with opposing qualities.

According to me all charter is needed. Similar interest is good for relationship.

Both couples and similarities of couple can maintain a long lasting relationship only if thye have mutual understanding between them.

Hmmm.. I think understanding each other is the basic thing which makes couple perfect. Me and my wife are two different personalities and have lots of dissimilarity but only thing is we listen to each other and respect views of each other which is the reason we are happy being together.

Love and understanding is important for good relationship.

Trust, understanding  are main for good relationship

Same interests or difference anything but the best and mutual understanding and love having couple will be the best couple.

Couples should have different interests but some common interests. Different interests means that there is uniqueness in relationship and each one admires other and some same interests will give the couple to take part in those interests together and spend some quality time.