Advices to make Warhammer 40k more interactive

Hi, My friends and I talked and did some research to see if we could alternate phases of a game instead of doing them all and then moving on to the opponent. The main problem we've been told about is that it becomes a game of cat and mouse and we've received a few suggestions:

-Roll a die at the start of each phase (the main problem is that this could ruin the planning and strategy through simple bad luck) -Alternate shooting phase for each unit (but some armies with more units would continue shooting after the entire opposing army has done so) -Use a CP type AOS system (but some uses could be too controlled) -Combine movement and shooting phase

So, what are your opinions? What system could work better? What would the flaws be? Is this even possible ?