i agree totally. patriot playground is quite easy in comparison... start with the one near supersave (up the hill) and work out ur own route.
Ride in the park: start with the one nearest you, then get the one in the island then head across to the west wall and collect three from there - this should give you some time
Dont forget multistorey mayhem (get in any stallion outside but near the multistorey) and work your way up (fairly easy this one)
Gripped: Definately the hardest - start (at the top) by the blocked off tunnel entrance by the dam and work your way across the top line on the cliff (dont collect the ones near the cliff edge yet). When u reach the end, turn around and collect the ones by the cliff edge and drop onto the road. Drive back across and work down the road (youll see what i mean) and then go down the cliff at the end. Collect the ones on the cliff and then go to the park 4 the last ones.
Having completed the game a few times now i now only do them with the handling cheat on. (if its your first run through the game dont...) this makes it much easier. otherwise just drive slowly. (incidentally, try and get one with a roof as it rolls better onto its wheels.