I prefer Kanji's looks (Prashant's) to DM's (Ronit) although Ronit is a good looking guy, especially with his moush (not too fond of him minus it though).
Kanji has that brooding quality about him and yes, his eyes are very attractive, not to mention his deep voice, all of which he puts to great use.
They have not discussed Kanji's age but he could well be younger than Moti (it is not uncommon for a younger man to fall for and marry an older woman). I dont think there is much difference in age between Moti and DM, maybe a year or so. It is strange DM got married and had a couple of kids before his wife got pregnant with Maulik and Moti was still unmarried at teh time. I would presume that the girl is married off before her brother, especially since she is older. Maybe Moti told her parents she wanted to remain an old maiden and then went weak in the knees when she saw the dashing Kanji and married him secretly.