How do you know where the .545 cam starts working? Have you run it? Do you have a dyno sheet? I run a similar cam and it starts working way below that. It makes peak tq at 3500RPM.
Depending on his combo it may feel lazy with 3:23 gears but not necessarily. Unless you have an OD transmission you are going to have to compromise. I've yet to see a 440 that felt lazy and was well tuned.
A loose convertor and steeper gears won't make more HP nor is it required for more HP. It totally depends on use, power output and where it makes toque as well as the overall combo.