Hey LindaBird !! Getting started and finding the right combination is always such a huge challenge !!! once you get the hang of things you will find vaping is really amazing.
I'm going to throw my 2 cents into the hat....
Me personally, my sweet spot is the Ego battery+510LR(Low resistance) atomizer+drip tip. I always get the best throat hit, vapor and flavor with dripping. some find dripping to be a hassle, but once you get the hang of it, it works great (for me anyway).
When I am out and about, I use the 510 Tanks(smaller version of the ego tank) with my ego Battery.
I have had the same problem you are having with both the ego and 510 tanks (less so with the 510's)
two things to try with ego tank cartridges: 1. only fill the tanks about 3/4 full, don't fill all the way to the top..seems to wick better. 2. using a very small pain of scissors or knife(very small). Gently insert the tip of the scissors or knife into the small opening of the tank to remove any excess rubber from the area the atomizer punctures the tank.......clear as mud?
Tanks are never my first choice for vaping....they are great in theory and when the work, they work great, but as you are finding, can be hit and miss.
All 510 atomizers, tanks, cartomizers etc will fit the ego battery.
You will end up trying many different systems and combinations until you find the right combination.
I have dealt with http://www.liberty-flights.co.uk/ in the UK and always had great products and service. They carry a bit of everything.
Just remember you Ego battery will work with many different vaping options.
I know your head is swimming, but I promise, it is well worth it !!!!