I'm not an expert, but I did start out the same way as you, with an eCab. It was and is still great, but I had the same issues, I was beating it to death so I needed to take the next step.
First I bought the eGo C type A tank tips starter kit with upgraded variable voltage 650 battery. These work the same as the eCab for filling and maintenance so it was easy for me to start out, the tips and atomizers are interchangeable with the eCab too so I thought it would save money. I found that I was still filling the tip tanks too often and was going through a lot of atomizers because they retain flavor when switching ejuices, (they can be boiled out but it's a hassle). I was till over using this device and getting a lot of juice/burnt taste, but it was fine if you don't vape constantly.
I then went to the clearomizers like the iClear 16 and vivi nova's, and screwed them onto my eGo batteries. These really made a difference, I was getting more vapor when I needed it and other than swirling them around to keep the wicks soaked they were great, but now I was using up my batteries because these run best at the higher setting of the variable voltage. (Variable voltage, Blue setting is 3.2volts, yellow setting is 3.7volts and then declines as battery begins to run low).
I then started looking into batteries, I ended up buying a 1000 variable voltage eGos pass through and an eGo 1000 twist. The pass through was so I could vape will recharging and the twist was so I could turn up the voltage to whatever my tank system needed. these worked well for me, and in retrospect if I knew better, I would have started with eGo Twists and stayed there, they have the slim look that doesn't feel awkward in public, but you can screw any tank device on them and adjust the voltage to what you need.
Then I bought bottom atomizer/wick clearomizers or tanks, no more tipping and burnt/dry taste but a more subtle vapor that took a little getting used to. They were easier to clean and maintain but had more leaking, gurgling issues. These were the T2-3's. Now I was in the realm of being able to rebuild my own atomizers if I wanted to and after trial, error and good advice, they stopped leaking/gurgling on me and became my go to for vaping.
Chain vaping now became possible and I now longer felt I wasn't getting the delivery I needed. Most of the gurgling and leaking problems were solved by going to a higher VG ratio, (thicker fluid), 30PG to 70VG and turning up the voltage to keep the atomizer from flooding or gathering condensation. This is where the twist paid for itself. I also changed the variable voltage on all my batteries to high and overnight my other issues disappeared.
I then went to the latest bottom atomizer tanks out there, (forgive my verbage if it is not correct, some call these clearomizers but I think a tank is a tank), The newest MT3's eVods and the Protank, (There are also equally good glass and plastic tank systems out there that work great, I just haven't got to them yet so I can't really give you advice), any well reviewed tank will do you well as long as you can throw the voltage to it it needs which means an eGo twist or larger battery.
There are many choices of battery out there and most of them are as thick as a Baby's arm, which is not for me, except when at home vaping. At the very least you need a twist and then if you don't mind being seen vaping a flashlight, the larger battery systems. I know I will end up with one of these soon for evening and weekend vaping but the one I want has issues with the finish wearing off at this time, so I cannot endorse it or purchase it.
This is my advice so far, you will need a larger tank system and a better battery. Entry level would be a eGo Twist with either a top/dual atomizer clearomizer or a bottom atomizer clearomizer tank system, and there are even cartomizer tank systems, (tanks with a slotted cartomizer in the center, the original tank mod). If you remember these specifics when doing your research it helps you categorize what you are looking at. All work well if properly maintained and you are willing to deal with each models specific foibles.
Hope this helps a little, just passing on what I have learned so far. Key words are MORE BATTERY, (higher voltage longer life), and TANK SYSTEM, (Top atomizer/Dual atomizer clearomizers, Bottom coil atomizer tanks, and cartomizer tank systems).
One more thing, just when you think you have found the perfect thing, someone is going to create something new to blow your socks off so be prepared to evolve with this new and ever changing market.
