Yeah, CE4s are kind of... meh. I use CE5s and do fine. Real easy to take apart (the parts just unscrew from each other, no tools needed), clean out, air dry, reuse. I had one CE4 and cleaning the thing was a total pain in the neck. I wouldn't recommend them.
And 2.4 ohm is fine. That's in the "standard resistance" range and work fine with the ordinary voltage ranges. The non-variable
batteries run around 3.7 volts. That's gotta be something about lithium ion batteries. If you check your cell phone (I mean one that has a replaceable battery, not the iPhone which I would not recommend trying to pry open just to look at the battery

), it's probably got a 3.7 volt battery too. The power charts put 2.4 in the "middle range" with that voltage. They'll be fine.
I use 2.4 ohms with my Twist which adjusts from 3.2 to 4.8 volts. Decided on 2.4 since it isn't likely to burn at any voltage in that range. That way, I wouldn't have to worry. Could just adjust to taste and not have to check a chart.
If you move to more advanced set ups like eVics and Vamos and Provaris and all, there's an additional learning curve there. Which is fine if you want to move up into the "advanced" realm. Just be aware. I'm more of the opinion that when you're "getting your feet wet", it's better to stick with the simpler systems. Move up later after you get more into how all this
vaping stuff works.
That last paragraph pretty much sums up my advice as well... getting better delivery devices (EVOD, Protanks, CE5s, Etc) will likely do more to help you now than to get a brand new shiny $50-100+ mod. When you DO decide to dive into the deep end, make sure you do your research and are ready.
As for B&M's, remember, these folks are looking to make a living as well as "help" you, so its quite often a case of buyer beware, as not all B&M employees will be on the level. I always take the advice of a B&M employee with a grain of salt (and a wedge of lime, with some tequila thrown in)
Of the better mods I can recommend (for when you're ready... I'm not saying to go get one right now, because it likely won't be of much help at the current moment.):
Provari: Ease of use, tougher than nails, Variable Voltage, gives a consistent vape throughout the life of the battery discharge (Many mods suffer from power loss as the battery gets drained.) More or less a lifetime warranty on these things, and you CAN send it in for repairs. Highest priced mod I'd ever recommend though. Make sure you're ready. Does need rechargable batteries. (size depends on model)
Vamo: Easy to navigate menus, pretty tough (at least mine is), variable voltage and variable wattage. vape quality seems good throughout the battery's discharge (I only really notice it start dropping once the battery hits about the 3.4v mark) Good price for what you get in a mod. Can sometimes find them in the $40 range. Does need rechargable batteries.
Itaste MVP: Solid little box mod. Easy to use Variable voltage. Built in 2600maH battery, with a pass-through capability. (which may or may not be a good thing, but at least you don't have to get batteries) Can often find these with a few of the Iclear delivery devices. Has the added benefit of being able to charge your phone off its internal battery if needed. Like the Vamo, I've seen these in the $35-40 range.
Vision Spinner: Variable Voltage Ego style battery (similar to what you already have, but with VV and a much heftier battery life.) Easy to use adjustment knob, easy to read markings. (I own three as backups of my backups) Usually in the $25 range.
Whatever route you decide is best for you, doing what you can (within reason, of course) to make sure the stink sticks aren't part of that route is awesome. Vape on brother, and sorry if we kinda overloaded you!!