J4 is my main, and fav support. His not in the meta, which is one of the reason I like him, and he is the first champ that inspires me to play support.
Mana? Not a problem, u run utility mastery, that gives u some help, and charm gives u some regen as well. Of course, if you spam ur skills, then you have problem like any other support.
No cs, his useless with out it! Well, his not, he has 3 cc and 1 adc buff and a skill shot debuff. Due to recent nerf, his flag now grants his adc AS (armor buff removed T_T), which is good. It also act as an temp long range ward, so you will never need to face check. Q+E is a free knock up or just mobility (over wall etc), well you need to practice you Q+E, but when E is down, your enemy will be cautions about you Qing as well, not to mention the armor shred with Q. W is AoE slow, but also a shield, this allows you to not die as often as a support (ignite? shield, over time damage? shield, ult in? shield.) AoE slow is also a nice gap closer if you don't wanna waste ult on like a 50% hp enemy. R, man my fav feature for J4. This ult is dangerous, for both your teamate and enemy, so you need to consider your moves really cautionsly. If execute properly, gg for champs that lost flash or have no over wall skills, but more importantly, I use this to trap multiple enemies (one is sort of waste unless it's a fed bruiser, who will be worth trapping), u might risk your own death, but let's just hope it will be worth it or if u have e q left, get out!
Now let's talk about tanky problem. There is no way wat so ever he will be tanky as jungle J4 unless ur team is fed, so let's assume a 50 50 team game. Ur priority is wards, but you don't farm, so u need philoso for regens and gp 10, like many other supports. mercury tread is the difference between J4 support an others where others will go for cdr (most of them). J4 needs to initiate, and not die, protect adc. Aegis(Runic), like other supports (taric style :P) will grant nice aura and self tankyness. Shurelya's also grant you more hp (cdr as well, and better initiate with active).
The biggest issue i heard is the healing problem, but seriously, not all supports heal. Like blitz, he provides 3 forms of cc (grab stun, knock up, AoE silent), with a speed up for offensive or defensive use. J4 has knock up as well, harder ofcourse, He has AoE "snare" and slow. But he has armor debuff and AS buff, as well has free flag ward, so he is no less than Blitz. If you compare him to like a naturally tanky support like taric, well his cc stronger than taric, he also has a buff to adc, so maybe a little bit worse, but still suit as support.