I started out with an automatic DSE-901. Over the years I've tried 510's, 801's, Janty Stick, Riva (eGo clone), 5V box mod, Provari, Lava Tube, Twists and most recently a Vamo. I've also tried a variety of juice delivery devices from carts/atty's to RBA's.
In your case I would recommend a 650mAh Twist with a Stardust rebuildable or a mini ViviNova. The 650mAh Twist is not too big but it delivers variable voltage and depending on your vaping habits it can last for several hours. As an alternative, look into some of the other eGo style VV batts (KGo, Vision Spinners, etc). The rebuildable Stardust is pretty trouble free, easy to fill, does not leak, provides decent vapor generation, and IMO looks best on and eGo battery. On the downside, the pull is tighter than I would like and some juices may crack the tank. The Mini ViviNova is similar to the Stardust but it has a looser draw than the Stardust. They both have replaceable heads that will last at least a week before having to be cleaned/replaces. If you clean them regularly they can last a couple of months. If you don't want to clean them, just replace the heads. They are only a couple of bucks so they won't break the bank.
In your case I would recommend a 650mAh Twist with a Stardust rebuildable or a mini ViviNova. The 650mAh Twist is not too big but it delivers variable voltage and depending on your vaping habits it can last for several hours. As an alternative, look into some of the other eGo style VV batts (KGo, Vision Spinners, etc). The rebuildable Stardust is pretty trouble free, easy to fill, does not leak, provides decent vapor generation, and IMO looks best on and eGo battery. On the downside, the pull is tighter than I would like and some juices may crack the tank. The Mini ViviNova is similar to the Stardust but it has a looser draw than the Stardust. They both have replaceable heads that will last at least a week before having to be cleaned/replaces. If you clean them regularly they can last a couple of months. If you don't want to clean them, just replace the heads. They are only a couple of bucks so they won't break the bank.