EricaKen

All of the members on the forum could throw recommendations at you, but the only one who can tell you what you like is you. Not that I'm trying to give you a hard time or anything but flavor is so subjective. What one person thinks is perfect, it will taste like dirty socks to the next person. It will all depend on what tastes good to you. One eliquid vendor I liked a lot when I first started out is EC Blends. They have little 5 ml samples for under three dollars (usually something like $1.99 or so). You can customize the juices as much as you like. My all day vape for several years now is an almond joy flavor. I would never have guessed I'd like it this much. Ever. You might surprise yourself with what you find tasty. 
If you want more throat hit, you'll want a little more PG in your eliquid. This is the flavor carrier, thins the liquid and gives better throat hit. If more vapor, smoother throat hit, a little sweeter, is your thing, then go a little more on the VG. For the set up you have I would recommend going with a 50 PG/50 VG to start. You don't want to go with anything thinner with that tank.
Also, at the beginning, go up a little on the nicotine. 3 mg isn't enough for someone trying to get off cigarettes. I'd go at least a 6 mg or 8 mg. If you vape too much and get too much nicotine, yes, you'll develop a headache. Just stop vaping for a little while and it should go away on its own. Make sure to drink lots of water. Vaping dehydrates you so increased water intake is a must -- not soda, not coffee or tea, or anything other than plain water. If the juice tastes a little "bad" when you increase the nicotine, then just have the vendor increase the flavor a little to mask it.
Hang in there, we've all been through it. The first few weeks are especially trying because your body is detoxing from all the carcinogens that you took in with cigarettes. If you can hang in there, this will pass.   

Like I said, keep your nic high. And flavor is important. If you don't like the juice you have, you won't vape it. Which also means you'll smoke.

It's totally normal to be craving. I smoked for 20 years but quitting and taking up vaping was easy for me, I was suprised. If you're looking for a good tobacco flavored juice try wrangler by vape wild. They have good juice in general. Also ejuice  connect has amazing prices. I've been vaping  for a year and just started craving tobacco  flavor lol. Especially when i drink. When I first started vaping  I stuck with high   nic   and tobacco  flavors. The key is finding  a juice that will satisfy  your cravings.