I’ve been toying with the following compromise for selecting tactics cards.
Apologies for the caps and Q/A style - just copy and pasted from the notes section of my phone (aka my beloved brain dump

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Q3: How do Tactics Cards work.
A: Tactics cards can be selected from those available in the base game along with any complete sets of gang specific packs in the following way
1) BUILDING A MASTER DECK. Each player makes a master deck of tactics cards as follows
— Mandatory: take a complete set of 10 generic gang tactics cards from the base game
— Optional: take complete sets of generic gang tactics cards from any supplement decks
— Optional: take a complete set of your house gang tactics cards from any base game or supplement decks
2) BUILDING A GAME DECK. Each player makes a game deck of 20 tactics cards as follows
— choose 10 cards from your master deck
— select 10 random cards from your master deck
The contents of each player’s master or game deck is open to all players.
3) AT THE START OF THE PRE-GAME SEQUENCE. Players may either retain their existing game deck or opt to rebuild it (once!) following steps (1)-(2) above.
4) During a game ALL CARDS ARE SELECTED AT RANDOM from the player’s game deck.
E.g.
Herbert has a Goliath Gang. It’s the pre-game phase of his first game.
He builds a master deck by taking a set of 10 generic gang cards from the base game, all 12 Goliath house gang cards, and all 10 generic house cards from both the Escher and Orlock Tactics cards supplement, giving him a master deck of 42 cards.
He picks his 10 favourite cards from this master deck, then selects 10 more at random from the remaining 32 cards.
Herbert now has a game deck of 20 cards.
He looks at them to see what he ended up getting from the random selection. His opponent also takes a look.
Herbert then shuffles his game deck and draws at random from it during the game.
Herbert doesnt like his game deck so much - it has both frag and melta trap in it - so in the pre-game sequence of his second game he redraws a new game deck following step (2). This new game deck is much better, so Herbert doesn’t bother rebuilding it for his third and fourth games today.
Herbert plans on buying the Van saar card supplement next week before his next game, so in his next pre-game sequence he’ll redo steps (1)-(2) to rebuild both master and game decks.