Fire can quite easily top the dps meters if you’re just going to pug anyway. Your problem is probably a combination of gear and skill, and I don’t mean that in a mean way. Let’s look at the situation a little bit closer.
First of all, what kind of content are you doing on your mage? Your ilvl is 186, so to compete, you wouldn’t want to go against people with +200 ilvl, because even if you played well you could still just lose because there isn’t a mathematical way for you to beat them on DPS. So before you get too disappointed yourself, try to see if you’re even having a competition to begin with.
Next point. You seem to be a fairly new player who hasn’t really been a DPS before, and on top of that you’re playing a new class and spec. I’d quite honestly be shocked if you could do your rotation without any mistakes. So yes, I’m also suggesting that you probably do need to work on your playing before being able to top the meters in any content. But don’t take it personally, very few people play this game or their spec correctly (hence why you’ll be able to beat them in DPS).
I guess in the end I’d definitely tell you that you’ve picked a spec that can quite easily top the meters when the gear and the skill come together. Getting to that point is the harder part. This won’t change no matter what spec/class you decide to play though, an element of mastery is always present. Going forward, I’d recommend a couple resources for you which you might or might not be aware of yet.
Warcraftlogs.com is a place for you to track your own performance inside raids. Simply search for your own character and then take a look at your logs. The numbers go from 0-100, with 0 being the worst, and 100 meaning you’re the best player for your spec on that fight. Aiming for a 99 is a good way to get better, as that means you’re in the top 1%. Read this to start logging your own raids
Raidbots.com If you’ve ever heard of someone saying to just sim it, this is it. You can download an addon called SimulationCraft on top of this, and with that you’ll just do /simc (copy all the data) and then paste it to the website. Quite easy to use on an elementary level. Whenever you get a new piece of gear, use this site to make sure it’s an upgrade.
https://discord.gg/makGfZA Is the mage discord. Place has all the best mages around the world, and a bunch of resources on top of channels where you can ask questions. No, voice chat is not necessary. They also have a bunch of guides and other stuff in the #resource-guides channel.
Spend some time to get familiar with these tools I’ve given you here. I would help you further, but I can’t without some data (warcraftlogs). Go do a raid and have a log, see how that goes. You can also use
wowanalyzer.com by yourself to analyze some of your mistakes, just know that this isn’t perfect. But to get rid of errors you could also analyze the best log on a fight by some other mage, see what kind of “mistakes” they’re doing to get an accurate idea of what you’re doing right and wrong.