Suzuki Gixxer

Since you haven't specified your budget, we'll recommend something that feels like a step up without hurting your wallet too much. You can take a look at the Bajaj Pulsar N160, Suzuki Gixxer 150 and TVS Apache RTR 160 4V - all three are comfortable and fuel-efficient machines which will feel like an upgrade over your Radeon. Do take a test ride and see which one fits you best, because your daily running is quite high. The Apache is a little cramped in the way it folds your legs, so you may want to take a look at the other two. 

Something comfortable in the 160cc space, like the Bajaj Pulsar N160, TVS Apache RTR 160 4V or Suzuki Gixxer will fit the bill for your requirements, although you may need to extend your budget a little bit for some of the higher variants. You can also look at some 125cc bikes like the Hero Glamour, Honda Shine and TVS Raider if you don't want to stretch your budget, but with two people on board, the 125s will feel a little breathless at highway speeds. 

A good upgrade without sacrificing mileage from your 100cc Platina would be something in the 150-160cc space, like the Bajaj Pulsar N160, TVS Apache RTR 160 4V, Suzuki Gixxer, Honda Unicorn/SP160, or the Yamaha FZ lineup. If you want to go beyond that, the TVS Apache RTR 200 4V, Honda Hornet 2.0 or Bajaj Pulsar NS200 will fit the bill. Take a long test ride to see which option suits you best.