I have mixed feelings towards using third party helpers. I don't recommend using them unless you're absolutely sure you know what they're doing. I've been helping troubleshoot Fedora systems for a while now and quite a few times, people break their systems and when you ask them what they did, they reply "I used $third_party_helper" which, quite frankly doesn't tell us anything.
If you know what the tool is doing, use it. If you don't, first find out and then use it. Generally, when you look into what it's doing, you realise how trivial it all is and you can just do it yourself. Use them because they are convenient, don't use them because you don't know what to do and they'll to everything for you.
Most third party helpers provide a one click solution to common tasks. I don't know what fedy does, but I'm quite certain it's just a frontend - everything it does can be done yourself. One perk of not using a third party helper, apart from knowing exactly what your system configuration is, is that you learn quite a bit. For example, if you take the trouble to set up RPMFusion yourself and install the media codecs, you learn why they aren't in Fedora in the first place - you learn what RPMFusion is - who maintains it - even something about how it works. If you use a third party tool, you skip all this important information - you just click and it does everything for you - you don't learn what codecs are exactly needed - it'll just install them all - you don't learn anything about RPMFusion - about packages forbidden in Fedora and so on. How many people know why there's an RPMFusion free repo and a different RPMFusion non-free repo? Did you know that there is software that even RPMFusion won't accept?
Basically, it pays to know exactly what your system is - what packages - what tweaks - everything. It's why we use open source software - so that we can look at the code and be completely sure of exactly everything that's happening. Sure, you generally don't look at the kernel code, but you can if you wanted to.
Fedy (Fedora Utils) is a great tool; as other great third party projects also includes the source code. Maybe need make rpm for some packages but is a learn process.