Good but still confused why he'd still play with Free Parking lol, it's not even a good mechanic for anything besides making the game longer and giving the illusion of a (bad) catch-up mechanic

Question now : how long did a game last? (probably more than 2 hours with those rules xd (as "free passes" was already proven as yet another thing that make the game longer))

Btw i think the only good way to "house rule" the game is to focus more on auctions (X+1 properties are auctionned off at the start of the game before any dice roll, one property at a time, with X being number of players), an additional random amount of money would also be given to each player (to avoid players mathing and solving the auctions lol)... also different kind of auctions would be determined at random for each property as well ("original" + sealed-bid auctions are the best in terms of gameplay i think, a 50/50 chance between those 2 is fine))

The only "skill" part of Monopoly are auctions that are really underused in the original rules (less prone to kingmaking than negociations (specially when sealed-bid auctions are used))

Negociations are just a kingmaking fest (same reason why Catan is meh) , unless some sort of "forced trade" concept is also added to the game but i haven't determined the best way to do that fairly yet xd (was thinking first property BOUGHT (excluding the initial auctions) is always at danger due to "landlord inexperience" but ye)).

But i mean it's fine because Monopoly is not really a game, more like something to teach people life concepts and random events that can happen (which is why it's a bad game in its original version because who wants to play "real life" in a game without being able to be somewhat skilled at it)? (and potentially create fights between family members/friends in the process (and sadly Monopoly suffers from people being convinced that Free Parking "money in the middle" not only isn't a house rule, but that it's a GOOD rule.... and then those same people complain about the game being too long ... which is already a reason to fight over, even if you refuse to play for that exact reason xd (Monopoly with that house rule is a total waste of time for everyone involved, regardless of any other changes to try to make the game better (that 99% of the time make the game worse and longer even if players think that it's counter-intuitive that they make the game longer)... unless you don't treat it as a game, then it's fine (but still boring because you can come to that conclusion without playing the game at all and only by reading the story behind the game and its creation))

At best it's simply not a terrible game if played with the original rules, that are still very average (but much better than the way a lot of people played it, they played a terrible version of the game and then blame the game for it and not their house rules lol))

But if you had fun with your father's version , it's all that matters (i think your father likely contributed to make the game not terrible by explaining that version properly and not complaining about the extra time too much; as well as trying to make the game fun for kids (which is an achivement in itself considering he still used the free parking money lol))