4. Costume And Art Design
The first thing that would need to go would be the Tardis exterior. Because viewers are morons and seeing something outside of their frame of reference will make them confused and upset, and cause them to change the channel, costing the network viewers and ad revenue. The interior would also probably be reimagined and have more of a slick
Star Trek feel to it rather than the whimsical and more organic feel of the current interior. And as for the tweed and bow tie, that would be out from the start in favour of something more fashionable and down-to-earth like a long black overcoat.