Really enjoyed the gameplay, art and h-scenes. Lost my first playthrough with Lia on final boss cause I had no shielding or healing and my deck was a mess. Can't say much about the story cause I skipped through most of it XD. I did get a few bugs like the pet's collar dropping on every elite fight in one of the areas rather than just the dog enemy. Nothing too game breaking mostly, got stuck at the end of a fight once with last enemy at 0 hp but nothing happening and just had to go back to main menu.
Then went with the minimalist deck approach and got a win on Felicia with just a raw dmg explosion deck and finally what seems to be the most popular Clara shield damage approach which really only needs 2 cards: the stable shield one and counterattack. Mine had 6 cards total at the end, 3 of which were exhaust cards.
I'll probably try replaying again later to try out other characters/ archetypes but my guess is that it's always going to be best to stick to a max 6 card deck for consistency, basically drawing and playing your whole deck every turn.
Edit:
Seems like starting with Willow is just a better version of any other strategy regardless what you want your end deck to look like, just cause she can infinite loop with the draw 2 discard 1 card she starts with and you just gene infuse whatever you want on to that card that you spam. Fastest scaling is still shield into deal 4x shield amount lategame afaik especially combined with the bond item that gives 6 shield every time you cycle your deck. Gene infusing mind pollute onto that cycle card combined with multi hit dmg cards is also pretty fast scaling. You can use felicia as your second to switch to her ult to constantly refill your energy so you can have a truly infinite loop with any strategy.
I haven't managed to find any interesting combos using intel sadly; explode, strength, consume, dmg x amount of cards and all the other strategies in the game all seem to pale in comparison to shield damage and mind pollute stacking but I'm sure I missed some op combos. There's also probably some decent ways to play a normal deck with a large amount of cards without cheesing everything with a 5 card deck but I'm too lazy
I'm not great at these games, but I do love them.
Anyway, It's common knowledge that minimalist decks are just better, but after reading what you wrote, let me just say 1 thing:
Clara is OP and can clear any fight in 1 round, even the last boss.
I tried to be a "purist" and only take cards from my main angel each time I played, so there must be better decks than mine, but still - Turn 1 win is good enough for me, lol.
All you need is:
Charge Up x 2 - For getting shields and Energy (I thought I'll need more than 1 round... so there are probably better options)
I fused them with Extra shield / draw / Reload.
Mutation (Clara Special) - Just in Case you'll get a bad starting hand, and it can also trigger a win with the right combo.
Defend - 0 Cost, Had it at start. Not a must but I put shield Enhance on it so it's quite nice.
Elemental Cycle x 2- This right here is THE card to win with. build up a few shields and use it, or double use it with Mutation. once will kill nearly anything that isn't the last 2 bosses, and by then you'll be able to use it twice or use the following cards.
Zero - If you use it after beefing up with Elemental Cycle, it will do Massive damage to finish off any boss.
Counter Attack - Because I wanted to have an attack that wasn't "Exhaust" just in case.
Static Electricity - Not needed. I thought I may need it for longer fights, but as I said - Turn 1 victory.
Angel Shadow - Willow Special, got it for the draws. You can also go with Felicia for that.
Most cards were beefed with extra shields / reloads. The shields are the important ones since they boost damage.
Get Hair Tie and Egg Gear for that extra 1st turn effectiveness. Flashlight Also fits nicely.
Edit: Oh and also get the gear Whip from Willow if you can, to get that "Heavy Hit" on turn 1 (which again, is all you'll need).