It's been a long time since I've been a noob player, so I'll make it simple. Rollers are the easiest way to go since they paint fast and get lots of points and kill people when you roll over them. Here's what most new players don't realize: swinging the roller is actually really effective for killing, and by really effective I mean less predictable. If you encounter an enemy, do not try to roll over them but rather stop rolling and start swinging. My apologies of you already realized this, but I'm always surprised by how many people don't and just keep rolling around.
Since you're still low leveled, you probably don't have much access to the better weapons, but when you do, I'd recommend to you the Dual Squelcher. It has an excellent range and rate of fire and beats out most other shooters with inferior range (although it does require some accuracy so make sure you've got that down first).
As for Chargers and Inkbrushes, Chargers are definitely hard to master, especially in Turf War where they really don't earn points that easily (but can still earn plenty if you're good enough). However, I wouldn't base your weapon choice entirely off of how many points it can earn in a Turf War. Learning a charger weapon early on will be extremely valuable if you ever try to pursue higher ranks in Ranked Battles. And for the Inkbrush, which is one of my favorite weapons, I can easily break 1000 points a match with it, but it obviously requires a lot of practice and experimenting with movement/positioning/etc.
Most people, especially those without prior shooter experience (myself included), have difficulty aiming more technical weapons like chargers and the .52/.96 Gal which is why the Rollers are always so popular. However, I would also recommend the rapid-firing, short-ranged shooters. Generally if you just stand near your opponent and shoot, the ink spreads widely in a matter that makes it difficult to miss and they are also well equipped to earn a lot of points. The weapons that fall into this category would be the Splattershot Jr. (your starting weapon), the Aerosprays, and the N-Zaps.
Lastly, it's totally fine to gravitate towards the weapons other people use. The crowd actually has an okay idea as to what weapons are good and easy to use, but of course it doesn't hurt to be different. Best of luck to you!