Remove coins. A mechanic that only exists to punish the player for not going out of your way to get them, and worse, punishes you for having the GALL to get hit by the inherently random items.
Fuck no.
Coins exist as a "investment" system. In Mario Kart 8, coins are often placed in sections where you have to be on a slightly less desirable path to obtain a large quantity, decreasing your long-term time for a short term speed loss from deviating from the optimal path. You must make this decision multiple times as coins are drained from you due to being hit by items, and it is a matter of skill to obtain the most amount of coins as quickly as possible for the least time cost. However, you must also anticipate other player's movements, and if a player right in front of you is going for them, you have to determine the accuracy with which he will hit all the coins ahead, and you either A) try and salvage as much time as possible by adjusting your course to a more desirable one or B) go through an alternate set of coins, as sometimes they run parallel to each-other.
And on the item complaint: much like a trading card game, where the creature/monster they draw is determined by chance but they will still beat your face in with some method, the individual items themselves are random, the probability you will be slapped in the face is near 100%. You're almost assured to lose progress.