Re: 'simple'solution
Tiny technical challenge, at midpoint the craft will be approaching the speed of light but I am a big picture guy I'll leave the fiddling details to others.
It takes approximately 1 year at 1G of acceleration to get close to light speed. A maximum distance flight to Mars (~2.5AU, with a little detour to avoid the unlicensed nuclear reactor between Earth and Mars) with 1G constantly accelerating and braking, would take ~4.5 days. Peak velocity at the mid-point turnover will be ~0.6% of light-speed.