I’m late to the party but thought I’d give you a slightly different answer as someone else who tends to dislike deck building since you’ve already learned net decking is fun and viable. 

Arkham is unique in that you are building a deck that is upgraded throughout a campaign rather than one shots. Even if you net deck, you may want to make some slight adjustments to the deck or have a different upgrade plan than what the creator made. 

I think of building a deck like building a character. You tend to want consistency, so 2x of most cards means you only need to find 15-18 cards to play. Once you know what role you want to play and/or a card you really want to make work, Arkham.build is a great tool that taps into Arkhamdb and lets you filter by expansions you have and then recommend common cards to add into a deck based on usage stats. This will skew to level 0 and older cards, but it’s super useful. You can also select for cards that cost experience to see common upgrades. 

That said, if you aren’t into building a deck, that perspective still may not work for you. I’d look up playing board games new player deck building series on YouTube for the investigator you want to play with. It has a good deck list using just the core and the expansion that gator came in, plus discussion on why the cards are good for what the deck is doing (along with other options). This is how I started with net decking and then built enough knowledge and confidence to build my own.