All the options you're looking at are really credible ones, but between them all, the Yamaha XSR155 makes the most sense. Since you have had little experience riding a geared motorcycle, something light, friendly, and easy to manage, like the XSR, is a safe choice.

 And because it shares a lot of its hardware with the proven Yamaha YZF R15 V4 and Yamaha MT-15 V2, it is bound to be reliable like its sportier siblings. 

Since this is your first bike, starting small and approachable would be the smart way to go about it. In that same vein, we would recommend the new Yamaha XSR155 because it is a light, comfortable, fuel-efficient machine that's also reasonably exciting to use. 

If you want a larger machine, then bikes like the Honda CB300F, Bajaj Pulsar N250 and Suzuki Gixxer 250 would be good options. 

Take a test ride of everything you shortlist before you decide. 

We have yet to ride the recently-launched Yamaha XSR155, so we can't comment on its ride quality just yet. However, the XSR is effectively a very comprehensively re-skinned MT-15. Our previous experience with the little MT, it had a well-judged suspension setup balancing both comfort and handling. 

We would recommend taking a test ride of the XSR if possible before you go ahead with your purchase. 

Of all the options you have shortlisted, we'd recommend choosing between the TVS Ronin, Royal Enfield Hunter and Honda CB350. 

This is because all three are proven products with reliable engines, two-up comfort and decent fuel economy. Coming to the Yamaha XSR155, that bike is a very new launch, although it does come with familiar underpinnings and a trusted Japanese badge on the tank, so we would recommend you take a test ride for yourself before you go ahead with your purchase.  

The new Hero Xpulse 210 is a good choice as it makes for a very comfortable city commuter as well. You might find the seat height a little tall, so we'd suggest that you take a test ride before making a decision. If that's the case, you could consider other motorcycles like the TVS Apache RTR 160 or 200 or the new Yamaha XSR 155 as good upgrades

The new Yamaha XSR 155 will have a more roomy and spacious riding position than the Yamaha MT-15. If you like the design, you can switch your choice. Given that this motorcycle is based on an existing and proven platform, there shouldn't be any serious issues, and you can make your purchase soon.