Try removing the roof trim and see whether the frame supports a possible place to install a roof lamp there. If there is, try getting an aftermarket or any cars roof lamp and fix it there. You can wire it via the original headlamp. I don't think anyone has tried but if you do DIY of it, then it would be of great benefit to all the Swift owners on his thread, given you share the method here
It NOT a huge problem for Swift to have a roof lamp as even City does not have one not even City Aspire A/T which costs over 1.8million. So instead of blaming Suzuki, the local industry should be blamed which does not encourage much advanced features in our local cars. The lamp is the least of our worries as Air bags is a much bigger feature missing.
I think Air bags is much needed feature as opposed to the roof lamp. And even if the imported Swift does not have one (im not sure), then its really childish to blame Pak Suzuki for that matter
Sir to let you know, Civic people could have you with it, because Civic comes originally fitted with it unlike Swift. So kindly refrain from bashing the members comments. Take positive criticism into account and learn from it. We are here to learn. Thank you and enjoy your stay here