Honestly, I wouldn't rely on either lulu or kayle support. they both work, but in the current meta, neither is especially strong.
Also, I might want to caution you on thinking that either of them would be spammable in all situations. Kayle is super easy to kill with nearly any mage pre 6, and even after 6 if you're behind. Lulu is very strong in lane, and in teamfights, but she loses if she can't land her skill shot Q, or gets outraged. A good lux, or morgana will wipe the floor with either champion, just due to their range. And those aren't the only ones, just the ones I play. I would take lux into kayle every day of the week and twice on sundays.
While both do have their roles, and are both useful champions in their own way, I would advise that it would be MORE beneficial to be able to play a wider variety of champs, at least 4 for each role. (Logic behind this : Ranked, you could get beat to the pick (1 down), and usually fizz/zed are banned (3 down) so you'd need a fourth. Now, the banned champs DO change with the meta, so take note of that as well. Normally, not more than 2 champs from a role are banned, unless the banner is super selfish and banning for his lane only. )
So, I would say pick up both when able, and also start playing free champs, at least in bots, to see who else you synergize with, and work towards getting them too.
For instance :
My champ pool :
Mid (main) : Lux, Morg, Ahri, Talon, Zyra, Swain, Karma, Lulu, Ori.
Support : Janna, Lux, Morg, Leona, Braum, Sona.
ADC : Cait, Lucian, Varus, Graves.
Jungle : Vi, Wukong, Shy, Lee, Kha.
Top : Irelia, rene, lee, Mao.
I'm not saying you'll be great at all of those immediately, or that some of them, like Ori, won't take a -very- long time to master, but it would be more beneficial to be good at a pool, and great at a select few. Obviously, by that list, you can see who I thought of first in each role. If I have a choice, those are my go to champs. But if not, I have others I can play.
Also, if you would like, you can add me, and ask questions. Or, I do mod a stream with a pair of DIamond's that might be able to answer questions for you as well :
http://boards.na.leagueoflegends.com/en/c/tips-tricks/W7KqoJiI-free-coaching-from-diamonds
They do free coaching on Saturdays (Sunday this week), but they're always willing to answer questions for you.
-T