1)maitri- if you cannot offer happiness, it is not true love. It is very important to share and spread happiness otherwise it will suffer. it is not important if it is romantic or not but it must be true.
2)compassion-It is a kind of energy that can help to remove suffering. it transform suffering in you and in other person and if you cant listen and feel suffering then it is not true love that is why 'karuna' is the second element of love and it should be cultivated by u and the other person.
ROMANTIC AND NON ROMANTIC THAT IS NOT IMPORTANT, WHAT IS IMPORTANT IS WEATHER IT IS TRUE LOVE OR NOT TRUE LOVE.
3)JOY-If by loving you make the other person cry all the time and you cry all the time that is not true love. love never become the reason to cry because it is the true form of happiness. romantic and non romantic it is not important
4)INCLUSIVENESS-you do not exclude his suffering is your suffering. There is no individual suffering and happiness any more in true love. Inclusiveness means non-discrimnation. There is no separation , no barrier between you and other person. In that spirit u never be in the you and me suffering or problems.
If romantic love has all these four elements, it can bring lots of happiness also.