Aseprite isn't free btw! But it is hands down the best program if you're trying to focus on pixel art.
Your choice entirely depends on your focused style - pixel art (piskels), vector (inkscape), bitmap/raster(krita)? If this is just a hobby, choose your favorite and go! If you're looking to make some income with your newly found art skills I recommend you get proficient with all three mediums but focus on the one that you most enjoy first. This will give you a foundation to branch out from.
As for which style is "better"...that's kind of an impossible question to answer. They're all equally a pain in the ass in certain departments.
Personally my setup at the moment is:
Affinity Designer - I think like $50 (Illustrator Alternative)
Affinity Photo - I think like $50 (Photoshop Alternative)
Aseprite - I think like $15
Dragonbones - Free (Bone / Mesh animation)
Audacity - Free (Music/SFX Editor)
https://www.bfxr.net/ - Free (SFX Creator for retro stuff)
VSDC - Limited Free (Video editor, doubt you'll need the full paid version but it's $20/yr)
Parblo Drawing Tablet - $80 (I do recommend a drawing tablet if you plan to create raster artwork from scratch, and take some free drawing lessons on youtube!)
Best Youtube tutorials for starting out, with making game assets, are by GDQuest - he even has some Construct 2 tutorials in there I think.