Why not the Oliver Hazard Perry class?
Because you don't buy a Ferrari for grocery runs. Moreso when you can't really
afford to sustain a Ferrari.
PN is not some blue-water navy with a need for fast transit across oceans,
and PH is not a global empire with a need to project naval power globally.
What PH has aren't even regional, but territorial defense concerns.
What PN needs are vessels more within the philosophy of an OPV:
good endurance+seakeeping; good sensories; economical operation.
Consider the likelihood that any OHP transfer will be very cold. If you
thought the Hamiltons were severely-stripped before delivery, hah...
Hamiltons have an autonomous 45-day endurance
Perry's require UNREP every 12-15 days, in a 180-day deployment.
[1]Both max out speed at 28 kts, but...
Hamiltons technically have a range of 14,000 NM at 11 kts
Perrys technically have a range of 4,000NM at 18 kts
'OHP' cost figures have already been posted, and the del Pilar opcost
(admittedly in a PN, not USCG context) is open source. Perrys do have
le two-car garage, which does affect endurance, but opcost-disparity
remains significant between an FFG and an OPV.
When/if fast vector is called for in a naval context, there should
be airpower on-call, almost inevitably land-based... which means said
airpower should have the range to get to where they may be needed
(our EEZ is a fair clue) ...and this is another cause of acute heartburn.
Get an OPV, but for God's sake, no more "fitted for, but not with" BS
which, for new-builds, stinks of a tactic to lower common denominators,
thereby enlarging the bidding pool and thus increasing the number of
bidders who might then try to bribe those in power.
[1] https://www.cbo.gov/sites/default/files/cbofiles/ftpdocs/104xx/doc10460/07-17-smallcombatants.pdf