The key to the coffee maker is water temp, too low, not enough extraction. I don't own any fancy drip coffee maker. I will say having gone through a few in my day. Having a good grinder helps to dial in the grind to your coffee maker. A technivorm brewer is on my wish list one of these days!!
The best thing I did to gain control of the roasting was heater control with a dimmer switch. This allows you to control the temperature during the roast.
At the rate of 100g at time an air popper is the way to go. Roasting in a popper is fast 7 mins or less and in my opinion creates a very bright cup. There are plenty of mods you can do to an air popper to control the chaff or even installing controllers, just search the net for "air popper...
Air poppers are totally gateway into needing more toys!!! You could always build an air roaster!!! I built mine for less than $200 probably and can roast 1.5lbs pretty easily.