What is the goal/concept of the modpack to make you consider the mods you want to include in the pack?
Whenever I make a modpack I have the goal first then spread the mods based on that goal or just ones I've familiar with/ones people haven't tried before.
Besides the title, and taking a look at the description it seems fine but if your unsure what to go about doing to add mods what do you want to include personally or for suiting the modpack?
Take a look at my modpacks and their various goals or updates/options more so than the version of Minecraft they are for as a reason but just a minor thing really and my 'average' logos I do put a bit of effort into besides what they look like. XD I am usually the type to make sure I have a goal first but not everyone needs one of course I know, I just find it helps so I don't go overboard or add to many mods I like instead of following the goal of the pack. :) I do make small enough to medium sized pack since I like to personally and hate overcrowded 100+ mod packs since I find them performance annoying as well as just never getting around to many of the mods sometimes, mainstream or niche downloaded mods.
Even my Puzzle Maps are generic but I loved the ideas behind them and put those into place more so than caring if some people want to see cool things appear in maps due to my beginner skills being clear but I had a strong focus on the concept/goal of the map and my own spin/attempt at such maps or things I hadn't encountered before with maps in the past.
Niche Mod Finder/Acknowledger/Tester/Player. Fan of Datapacks, Rift 1.13/1.13.2 Mods, Fabric 1.14 Mods and interesting underrated or new 1.12.2 and below versions of mods. :) Testing 1.13.2 Forge and Fabric 1.14 mods mostly though.
I sometimes create the odd modpack or adventure map once an idea comes together.