after 30 plus yearsof flying twins you are right about reliability and i have proiven that on all the twins i fly but murphy.s law comes into play also and since this is a new plane from cratch,my plans i am trying to make compensations for the inevitable one engine thay will happen,i have also found that overpowering a twin causes the deathroll much quicker than one that is powered right.back in 72 i built a 48 inch twin wing derringer from scratch.powered by 2 s.t g-15,s.this flew as your described b-25 when an engine was lost.however replaced the st 15 ,s with os 10's and when an engine quit on climbout right sfter takeoff and thge deathroll started,cutting power stopped it immediately.plane leveled off on its ownmade one turn into good engine and landed.there is an area where too much power causes problems also.as a desinger it is my job to try and eliminate problem areas.hence this post.