Main things to keep in mind while designing this 3D printer:

1. be able to print high peformance engineering plastics
2. it's gotta have a heated chamber(upto max. 150 degree celsius)
3. it has to be a dual extruder
4. it has to be direct drive
5. it has to be safe to use
6. accurate, reliable, ergonomic, aesthetic and affordable.

Main design features considered:

1. core-xy mechanism- for keeping the kinematics simple, and reduction of moving mass and to keep the motors outside the heated build chamber
2. heated build chamber - up-to 150 degree Celsius. this is required for printing in peek or ultem
3. heated bed - this is a common feature in all 3d printers and shall remain as it is
4. linear rails for x and y axis - MGN15 guide rails and blocks for achieving high positional accuracy, speeds and load bearing capacity.
5. smooth rods and ball-screws for z axis - 16mm smooth rods and LMK16LUU bearings because they are easy to work with , and ball screws because of their efficiency (it can be substituted with lead-screws as well , should not be a problem)
6. nema23 motors with ~20kgcm torque, so that there is never a step loss.
7. insulation of all mechanics and electronics from the heated build chamber, because i cannot expect the belts and bearings to work at 150 degrees. thinking of using glass wool for this.
8. 4040 aluminum extrusion frame - because it is easy to work with and is very rigid.
9. Duet wifi as controller - because it is 32-bit, and highly recommended by current users, and because it has Trinamic drivers with 2.6Amp capacity.
10. 7" PanelDue touch screen interface
11. all machine parts are milled aluminum for material uniformity . so that there are no uneven thermal expansion issues.
12. It has to be build at lowest possible cost, but without compromising on quality, hence making it affordable.
13. water-cooled hot end - with chamber at 150 degrees Celsius i cannot think of air cooling at all.
14. pause on filament runout

Other surprising features: (going against the tide)

1. no automatic bed leveling - because i absolutely hate software compensation for bad hardware. i just believe that the hardware had to be just right, and if its not then fix it, not compensate in software.
2. minimum software compensations - no skew correction.

Features i need but do-not know how to implement: (these are advanced features and are not needed to run the machine)

1. power panic
2. laser filament monitoring