I’ve been liking the name [name_f]Felicity[/name_f]. [name_f]My[/name_f] husband’s family is heavily into nicknames though…
He’s not crazy about Fee/Fi/Fifi
But, is cece/cici too much of a stretch? Also not sure, but would you pronounce cici and cece the same?
[name_u]Or[/name_u] Issy/Izzy to much of a stretch?
I don’t like Flossie/Flo/Flick unfortunately.
Let me know what you think!
[name_f]Felicity[/name_f] is lovely!!
[name_f]Cece[/name_f] is definitely Cee-cee to me but [name_f]Cici[/name_f] could be Cee-cee or sis-ee - maybe the latter with [name_f]Felicity[/name_f] but either work 
[name_u]Issy[/name_u] works to me.
Some I like for [name_f]Felicity[/name_f]:
Fliss
[name_f]Lissy[/name_f]
City
Effie/Effy
[name_f]My[/name_f] favorite option is [name_f]Lizzy[/name_f] so I definitely think [name_u]Izzy[/name_u] works.
[name_f]Lissy[/name_f] is a fave of mine! Like [name_f]Lizzy[/name_f] but with an ‘s’ sound rather than ‘z.’ Perhaps also: Fels, [name_f]Fella[/name_f], [name_f]El[/name_f], Fitty, Flitty, or [name_f]Cece[/name_f].
I really like Fliss and [name_f]Lissy[/name_f] as nicknames. I guess [name_u]Izzy[/name_u] can work, but maybe isn’t quite obvious how can [name_u]Izzy[/name_u] work. [name_f]Flossie[/name_f] and [name_f]Flo[/name_f] are [name_u]Florence[/name_u] nicknames, [name_f]Flick[/name_f] works, but I understand why you don’t like it. I would pronounce cici and cece with different vowels.
other nicknames:
[name_f]Effie[/name_f] - kind of like [name_u]Fee[/name_u] but more pronounced
Felly
Fitty
Fessy
Litty
I think I am also adding Fizz to the list!
The first nickname I thought of is [name_f]Lissy[/name_f], which I think is adorable!
I’d go with Fizz/Fizzy, [name_f]Effie[/name_f], Flissy or [name_f]Lissy[/name_f] 
I like [name_f]Lissy[/name_f].
I love the name [name_f]Felicity[/name_f]! [name_f]My[/name_f] favorite nicknames for it are Liss, [name_f]Lissy[/name_f], Fliss, and [name_u]Felice[/name_u] (fuh-liss). I think Fel or City could make a spunky nickname! I don’t think [name_u]Issy[/name_u] is a stretch, but [name_u]Izzy[/name_u] may be. [name_f]Cece[/name_f] or [name_f]Cici[/name_f] wouldn’t be a stretch at all; I generally do pronounce them the same, but [name_f]Cece[/name_f] is always “see-see” and [name_f]Cici[/name_f] is both “see-see” and “sissy”.
I do like the “see-see” pronunciation better so I’m leaning toward [name_f]Cece[/name_f]
This might be a but if a stretch for you but how about [name_u]Lucky[/name_u], considering [name_f]Felicity[/name_f] is derived from the Latin ‘felicitas’, meaning ‘luck’?
[name_m]Fitz[/name_m] 
I think [name_f]Lissy[/name_f] or [name_f]Lissie[/name_f] is the most obvious nickname and is a similar style to the full name (both sound very dainty and old fashioned). I do think [name_u]Izzy[/name_u] is too much of a stretch, most people would assume her full name was [name_f]Isabelle[/name_f] or [name_f]Isabella[/name_f]. I think [name_f]Cici[/name_f] or [name_f]Cece[/name_f] could work though
I would say [name_f]Cece[/name_f] and [name_f]Cici[/name_f] the same way and don’t find them at all a stretch though with [name_f]Felicity[/name_f] I would choose [name_f]Cici[/name_f]. I also think that [name_f]Lissy[/name_f] would be a good one.
Lishi! (lish-ee)
Kitty/Kit
Fea/ Feia/ Fei
Itty/Itsy/Etsy/Itta/Etta
Fitsy/Flitsy/Flitty
Lacy/ Lessie
Lika
I used to know a [name_f]Felicity[/name_f] who was [name_u]Izzy[/name_u] to her mates.
Equally, Flicka is brilliant (reminds me of that pony film!)
Fliss, [name_f]Sissy[/name_f], Fizzy are also great
Went to school with a [name_f]Felicity[/name_f]. Everyone called her Fliss or [name_f]Flick[/name_f].