This made me chuckle in a good way. Our group has started doing same project and we've also decided that LD test with penalty for dead fighters is the way to go! If 2 different groups think of the same idea, then it is has to be good.
We've decided to go with Shadow War: Armageddon way of approaching juves. Juve can't buy advancements, but for 10 xp points he can become a ganger, upgrade his statline for free and change equipment once.
We also made every gang have the same stat line. However, every gang gets "thematic" advance, STR for goliath, I for Escher, M for Delaque, LD for Orlock; Cawdor gets nothing, but it means that their fighters are cheaper and thus easier to spam, Van-Saar get built-in Undersuit (and we've removed undersuit from game) while having different prices for armor to acommodate for +1 save. You can pick 2 types of champions: +WS and +A one or +BS one.