Is this new tank design good?

The first image is the old tank design that I made cheap. People said the armor wasn’t needed though as I’m in single player and 12 km speed to match my divisions. So my new design had a 70 armor threshold, passes the 80% reliability mark, has 12km of speed. And it was 18 production cost (a single line of this tank can make 23 of these a day) Is this a good design for single player? If not what should I sacrifice for quality in exchange for higher production cost