Cato: an original card game

I invented this one years ago and had forgotten it until recently. I can't claim much originality for it: I just thought it would be fun to take Ecarté (an unjustly neglected game nowadays) and combine it with the card-point system of games like Skat and Sixty-Six.

Cards: 32, ranking and counting as follows: Ace 11, Ten 10, King 4, Queen 3, Jack 2, 9-8-7 zero each. The total value of counters in the pack is 120.
Deal: Deal five cards each, singly, turn the next face up to establish a trump suit, and stack the rest face down to one side. The point-value of the trump turn-up (if any) will eventually accrue to the winner of the last trick.
Object: To become the leader and, as such, to capture in tricks at least 31 card-points and more than your opponent.
Bidding: Non-dealer may either become the leader by leading to the first trick, or "propose" an exchange of cards. If dealer accepts a proposal, there is an exchange of cards as described below and the process is repeated until someone leads or not enough cards remain in stock. Alternatively, dealer may refuse the proposal by simply leading to the first trick.
Exchanging: If both agree to exchange, each in turn, starting with non-dealer, must discard from one to five cards face down and draw the same number of replacements from the top of the stock. Neither may take the turn-up, and non-dealer must leave at least one downcard covering it.
Misère: If neither player will lead when there are no cards left to draw, non-dealer leads a card and the object is reversed - that is, whoever captures the fewer card-points scores the total value of all those in play, including the turn-up.
Chicane: If your opponent leads and you have no trump in your hand, you may, before responding, exercise the privilege of "chicane" - that is, show your hand, discard it entirely, and replace it from stock. You may repeat this so long as your hand remains chicane and one or more downcards remain in stock. If fewer than five remain, only that number may be exchanged.
Play: You must not only follow suit if you can but must also win the trick if you can. If unable to follow, you must trump if you can. Only otherwise may you freely discard. The trick is taken by the higher card of the suit led, or by the higher trump if any are played, and the winner of each trick leads to the next.
Score: Both players count the number of card-points they have taken in tricks, including that of the turn-up for the winner of the last. To win, the leader must have a higher total than the other, and that total must be at least 31. If that is the case, both players score their respective totals. If the leader fails - whether by not taking a majority or by not reaching 31 - the leader's score is zero and the non-leader scores the value of all card-points in play, including that of the turn-up.
Game: The first to reach or exceed 121 points scores 1 game point if the other has at least 91, 2 if under 91, or 3 if under 61. The overall winner is the first to attain 3 game points.