I assume you've tried keeping him awake for a reasonable period after a feed before attempting feed/rock/cuddle him to sleep?
After so many weeks as a newborn, it did come as something of a shock to me that DS suddenly needed entertaining after feeds. He's only a shade over 8 weeks and will happily stay up for 1.5-2 hours at a time (so around 45-60 mins after feeding).
He takes two 45 min naps and one longer nap (in my head 2 hours, but actually about 90 mins) during the day. He doesn't always go straight down at 7pm (rarely does), but increasingly when he doesn't he's just staring around him, rather than crying, and is usually asleep by 9pm at the latest.
Does he feed well during the day? If he's just taking a little feed, it's likely that he'll want to just catnap straight afterwards and then feed again soon afterwards, and continue this trend into the night. Not that there's any problem with that if it suits you, but if it bothers you, it might be worth encouraging him to take bigger feeds if you possibly can? My DS is big and greedy, so takes both sides and feeds for an hour each time, and feeds at roughly 7:30am, 10:30am, 2pm, 5pm (split feed with bath), 10:30pm and 4:30am. I think that's less frequently than many manage though - I put it down to him being piggy enough to take a monstrous feed when he does feed!
Saying all that, if he's happy, and it's not driving you mad, there's no reason to change anything! You only need to change things if they're not working for you or your DS.