First off, leave the economy. If one can afford 19 Lacs for a car, then I don't think 300-400 Rupees extra every refuel would be a problem.
As for the feel, the Gli Automatic isn't too bad, but the problem is you'll have to floor it and wait a second or two for the engine to kick in during overtakes, but in the manual, you can do a lot more. You can fly through traffic, practice shifting, do wheelspins if there's a City next to you on a Red Light haha. But anyways, go for a manual, you won't regret.