increase minChangeTarget to 10kas

cmd/kaspawallet/daemon/server/create_unsigned_transaction.go

@@ -15,9 +15,12 @@ import (
 )
 
 // The minimal change amount to target in order to avoid large storage mass (see KIP9 for more details).
-// By having at least 0.2KAS in the change output we make sure that every transaction with send value >= 0.2KAS
-// should succeed (at most 50K storage mass for each output, thus overall lower than standard mass upper bound which is 100K gram)
-const minChangeTarget = constants.SompiPerKaspa / 5
+// By having at least 10KAS in the change output we make sure that the storage mass charged for change is
+// at most 1000 gram. Generally, if the payment is above 10KAS as well, the resulting storage mass will be
+// in the order of magnitude of compute mass and wil not incur additional charges.
+// Additionally, every transaction with send value > ~0.1 KAS should succeed (at most ~99K storage mass for payment
+// output, thus overall lower than standard mass upper bound which is 100K gram)
+const minChangeTarget = constants.SompiPerKaspa * 10
 
 // The current minimal fee rate according to mempool standards
 const minFeeRate = 1.0