That mirrors what I'm hearing from some people that have a PS4-P as well. Some games are better, but some actually perform worse at 1080p on the PS4-P compared to the PS4. One person I know even went so far as to say one game (forgot which one) actually looks worse on PS4-P on a 1080p TV than a PS4. They were mostly disappointed in some of the Sony exclusives, but were hopeful that more games would adopt what a few games are doing in offering a 1080p/60 FPS mode instead of, or in addition to, a 4K mode or a 4K downsampled to 1080p mode.
If Bloodborne would have gotten updated with a 1080p/60 FPS option on PS4-P, I'd be really tempted to get one, but alas it appears that From Software have said they have no plans to offer a PS4-P upgrade for Bloodborne. It may also not be possible for them to offer a 60 FPS mode on PS4-P as they use a heck of a lot of physics simulations in that game, which means it's likely CPU bound.
Regards,
SB