I’m looking for names in the same style as [name]Niko[/name] (for a boy). [name]Love[/name] the name but can’t really think of any good names that go nicely with it should there be another boy or two. Help! 
[name]Luka[/name]… I know siblings that are [name]Nico[/name], [name]Luca[/name] and sister is [name]Bianca[/name]! There are plenty of options to go with [name]Nico[/name] or [name]Niko[/name]!
[name]Niko[/name] &
[name]Adam[/name]
[name]Benji[/name]
[name]Cole[/name]
[name]Dimitri[/name]
[name]Demos[/name]
[name]Elias[/name]
Hawley
[name]Ivo[/name]
[name]Joel[/name]
[name]Johan[/name]
Greek:
[name]Atticus[/name]
[name]Augustin[/name]
[name]Basil[/name]
[name]Christos[/name]
[name]Cosmo[/name]
[name]Damian[/name]
[name]Elias[/name]
[name]Matthias[/name]
[name]Nicholas[/name]
[name]Orion[/name]
[name]Theo[/name]/[name]Theodore[/name]
Other names ending in O that remind me of [name]Niko[/name]:
[name]Arlo[/name]
[name]Alessio[/name]
[name]Amedeo[/name]
[name]Cisco[/name]
[name]Enzo[/name]
[name]Hugo[/name]
[name]Leo[/name]
[name]Laszlo[/name]
[name]Lorenzo[/name] (nn [name]Enzo[/name])
[name]Matteo[/name]
[name]Milo[/name]
[name]Rio[/name]
[name]Viggo[/name]
More that remind me of [name]Niko[/name]'s feel:
[name]Nicolai[/name]
[name]Dante[/name]
[name]Joaquin[/name]
[name]Roman[/name]
[name]Stellen[/name]
[name]Willem[/name]
Good luck!
I know a [name]Nicolas[/name] who goes by [name]Nico[/name], and I prefer this to straight [name]Nico[/name] (or [name]Niko[/name]).
With this ([name]Nicolas[/name], nickname [name]Nico[/name]), I like [name]Darian[/name], [name]Jamison[/name] ([name]Jamie[/name]), [name]Lucian[/name] ([name]Luc[/name]), [name]Leopold[/name] ([name]Leo[/name]), [name]Remington[/name] ([name]Remy[/name]), or [name]Roderick[/name] ([name]Rod[/name]).
If you just want to use [name]Nico[/name] - I prefer this to [name]Niko[/name] - other boy siblings could be [name]Brando[/name], [name]Carmine[/name], [name]Darin[/name], [name]Enzo[/name], [name]Gianni[/name], [name]Rocco[/name], [name]Cirocco[/name] ([name]Rocco[/name]), [name]Enrico[/name] ([name]Rico[/name] - rhymes), [name]Matteo[/name], and [name]Romeo[/name].
If you like Biblical boy’s names you could use [name]Nicodemus[/name] (nn [name]Nico[/name] or [name]Niko[/name]) and then lots of other biblical style names would work for future siblings.
[name]Levi[/name] jumps out at me as going with [name]Niko[/name]