I would like to improve the brakes on my wife's Cannondale CAADX 105 2016 cyclocross bike. It's only used for very light touring and short day rides on tow paths etc., but she isn't confident that the brakes can quickly stop the bike if need be. The bike came with Promax Render R, 160mm front and 140mm rear rotors. It is obvious from reviews that these are budget, poor performing brakes. I would like to upgrade the brakes and am thinking of the TRP Spyre as the most cost effective option but as someone who has never fiddled with disc brakes before am unsure about a few things before proceeding and would welcome any advice or encouragement. Do I just replace the calipers but retain the existing rotors? Or do I replace both the calipers and the rotors? The TRP Spyre caliper and rotor sets seem to be 160mm rotors so would I be correct in thinking that if I tried to replace the 140mm rotor and caliper with a 160mm set then it wouldn't fit? I'm keen to have a go at this - or do you think I should take it to my LBS? Any advice gratefully received.