Striking fish for a peaceful community tank...

Hi,

I'm setting up a 120 litre planted community tank in which I'm going to
keep Rummynose Tetras, Lemon Tetras and Endlers livebearers (Poecilia
wingei) with a Khulii loach, some corydoras and amano shrimp. I would
like to keep one or two more striking fish too but they would have to
be peaceful towards their tank mates.

The options I've thought about a
(1) Betta splendens (since I've always adored bettas - I do already
have two in other tanks.)
(2) A pair of Honey Gouramis
(3) A pair of Kribensis. (I'm not sure these will be OK with such small
ultra-peaceful tank mates since they can get up to 3 1/2 to 4 inches in
size. Also, despite their reputation for being relatively peaceful,
being cichlids I suspect they will still guard and hold a territory
quite aggressively if they breed. I do have a 15Gal (UK) tank which is
currently empty so I could transfer them if their aggression gets out
of hand. I don't know, maybe this idea is a non-starter.)
(4) Killifish
(5) Apistogramma Dwarf Cichlids
(6) Something else...

Any ideas, comments, or thoughts would be most welcome!

Thanks

Muddy