There are so many other factors than the gantry design in designing a CNC router to perform the operations you make highly generalized allusions to that it would be impossible to provide a reasonable response with any basis in fact or possibility.
Further, for anyone to make these voluminous design decisions for you would be an untoward and unnecessary expenditure of time on anyone's part, including yours, considering the time it would take you to interpret and correlate them into a unified whole.
There are more than enough builds detailed on CNC Zone for you to ascertain the design characteristics and performance potential that meet your initial hypothetical needs.
One clue though: Start at the tool tip.
Best of luck in your future endeavors.