The Triumph Speed T4 is a great bike in its class and one you should certainly consider. In a few months, Bajaj will be downsizing all the 400cc Triumphs to 350cc in order to benefit from the new GST 2.0 structure, and it remains to be seen how the T4 fits into this new lineup.
Similar bikes to the Speed T4 are the Royal Enfield Hunter 350 and Honda CB350 models, although their simpler, air-cooled engines offer significantly lower performance but have a deeper, thumpier exhaust note and more laidback character. This could be a good thing depending on the sort of experience you’re after, so take a test ride of these bikes before you decide.