Is my filter enough for me?

Well you can never have too much filtration capacity really , although you could have too much flow created by an oversized filter. I've never used that particular filter so I can't comment on it specifically. I always like to have two filters, mostly as an insurance policy against a failure, so that would be my only recommendation. A nice HOB style filter would be a good choice as a secondary filter.

Most gph ratings on canisters is computed without media. That is with just water flowing through the hoses and empty canister. I as do allot of people prefer to turn the water column over 8X10 times/hr. I suspect you really need more surface agitation than that canister can produce. +1 on above comment. An HOB added would be good.

HOB stands for hang-on-back, Aquaclear is one example, as are the biowheel type. Which you buy is a matter of personal preference, but any of them can/will work for you.

I run the penguin bio wheel 350 along with my canister. Lots of surface agitation

any tank over 20 gallons should have two filters running. once you get to the larger sized tanks, you tend to stock more/larger fish. if your only filter konks out, you are left with the equivalent of a giant fish bowl, and rising ammonia, until you can fix or replace that filter.

my 55 gallon has an aquaclear 110 (hob filter) and a rena xp4 canister. i have enough filtration for a tank more than 4 times the actual tank size. i never look at the gph, but at what size tank the filter is rated for, and aim for at least 3 to 4 times the filtration size for my tank. gph is drastically reduced once you put media in the filter, so IMO it is not the best guide to use when deciding on a filter for your tank. that gph is variable depending on what media and how much media you cram into the filter.

my 20 gallon long planted tank has a 55 gallon hob filter on it.

you can never over filter!

There is an on-going myth or misconception that we need 4 to 10 times the tank size in gallons per hour (gph) filter flow. Granted that filters are flow rated without the restriction of media, however media is taken into account when tank size recommendations are made.
Personally, I think that filtration really needs to be less about water flow and more about filtering the water through very fine media.
I also think we just might miss the mark attempting to trap most/all detritus in the filter. Detritus and mulm on the substrate very slowly decomposes to feed the bacteria and subsequently any rooted plants. In the filter, through accelerated decomposition and water erosion, the detritus is quickly converted into dissolved organics that pollute the water. The tank may 'look' cleaner, but the water really isn't.
Finally, many/most aquarium filters may trap some detritus and provide some bio-filtration, but may fall way short of water purification. For this we really need to leverage chemical filtration to adsorb impurities. Many have sworn off the use of activated carbon because it's useful life is somewhat limited (relative to the impurities it adsorbs). However, activated carbon has been used for decades to purify water...and is used in most filter systems used to purify drinking water!
But I digress.
It seems to me that if we're filtering the water very well, we probably only need to filter every drop a couple of times per hour....not 10 times! Not to mention that very high flow rates are very stressful to fish not accustomed to raging river like conditions.
Frankly, many with heavily planted tanks that perform 20-50% weekly water changes, find they only need a very modest sponge filter, rather than a canister, a HOB or both.
The bottom line: More water flow does not mean better filtration as water quality is determined on how well we filter the water! Typically, you can use the manufacturers recommendation for filter/tank size (and often even less).