Physical shape or appearance of the spouse might have a little effect in making the marriage more happy at the beginning but it will never last for long, nor can alone create happy life. You wrote : I am content with all besides her weight. This means that she has got many good characteristics besides her weight. I advise you to focus on her good points and ignore her weight. Her good points, noble attitude, good heart, humbleness, sincerity etc, will make your married life happy and not her weight. Men who focus on physical appearance and ignore the heart and noble human essence never get the happiness and satisfaction. Be content with whatever Allah Has granted you and thank Allah (SWT) Who granted you a noble and clean hearted wife who should be a good mother for your children and don't focus in her weight at all. When you thank Allah for the good that she already has, Allah will grant you more happiness from unexpected bounties which you don't know now.

Wassalam.