Nice takouba! To answer your questions:
1. The tip profile is seen on quite a few takouba. I think its a combination of intentional reprofiling and sharpening. I have speculated in the past it might have some sort of function in the Sahel areas that used heavy, quilted fabric armour. However that's a bit at odds with how takoubas seem to have been used - mainly as slashing weapons. I've seen it most on Hausa swords - but that's not to say it couldn't exist on others.
2. Late 19th to early 20th century seems possible for this piece. Better photos would help.
3. Are there any decorative elements on the brass hilt? Is there a mixture of copper and brass plates on the pommel stack?
Takouba are somewhat hard to pin down ethnically simply because of the interconnected nature of the kingdoms and areas were they were used.
Overall this looks to be a nice sword and one I would be proud to have in my own collection. Thanks for sharing.
