Considering your usage and budget, you can look at bikes like the Royal Enfield Hunter / Bullet / Classic 350, Honda CB350 trio, TVS Ronin and the Hero Xpulse 210. All have spacious seats, comfortable suspension and have decent braking performance too. A test ride of all these machines with your wife sitting behind you will help you decide which is the right fit for you.
Do bear in mind that making the switch from a scooter to a motorcycle will need good hand and foot coordination to operate the clutch and gear pedal. We recommend you practice on a used bike first before taking the plunge.