HAA, Hillsboro, former HAI,
have run THIRD base/location in Prineville, Eastern Oregon for couple years by now. This is exactly for the reason some feel their progress may be hindered. Helicopter flying wise, SVFR is just fine for local patterns, although there are too many students to fit into those so they have to 'ferry fly' elsewhere for circuits/patterns and autos.
Fixed wing/aeroplane wise, indeed, the NW Pacific winter with icing ceilings, low cloudbase or fog indeed make for different winter than Florida. Eastern Oregon is 'high desert' climate different to coastal areas. Lot drier and sunnier. I flew along Columbia river and it's different picture passing the Gorge suddenly.
Mind you, I never spent time in Oregon not within May to October. The early autumn weather is fairly OK still, early morning inversion/fog lifting up, if no frontal crap passing through or low pressure area sitting overhead.
Have you counted in the sales tax in Florida to your costing for living expenses? No sales tax in Oregon. That applies to RENTAL/solo flying also, not just food/petrol. Do ask HAA about the fuel surcharges as they don't include it in quotes. Adds up.
Hillsboro and airports in area have plenty and variety of IFR precision or non-prec approaches, there's the coastal range misty IFR to plan for if going over, not far from Northern California or WA state if doing longer XC trips. PDX if flying faster ship like a twin for missed approach practice, even.
Mountains, rivers, gorgeous summer, variety, neighbouring states. Do you get that somewhere in flat southern Florida? Where you'd be suffocating from humidity half of the year out on the ramp/ground, unable to fly part of the day during thunderstorm season and wishing for winter.
If you're going to US specific month, then maybe consider the initial training VFR weather etc, but West and NW of US is definitely more useful. Some Midwest places with high DA all the time may teach you to be cautious about PA/DA, keeping speed, calculating performance etc, but they'll have VERY hot summer. Still better than Florida.
Wanting Asian students/cadets around? Almost any big school in the USA, honestly. I'd actually say that it may be better to avoid/reduce exposure due to improving aviation English. Some Japanese students shouldn't even be flying solo or passing checkrides but that's another story and no point digging into it. Have heard first person or own experience that reduced safety.
One can also fly out of Troutdale with HAA, but I recommend HIO for exposure to bizjets, Kingairs, housing cycling distance from airport, more complex airport, better approaches/STAR/SIDS right there, Newberg VOR will be your new best friend on IAPs. Troutdale isn't as busy as HIO, less turning and burning on taxiway. It can get tiring. OTOH, you got PDX upside down cake with glidepath near, the Cascades around the corner. More limiting.
Your call, just consider the downsides of Florida. I spent summer around Atlanta ages ago and that's still inland and further North than most of FL and the only acceptable heat/humidity combination for me started in October, ehrm. Seeing your original location, you may be fine with tropical weather, for many Europeans it gets tiring as one doesn't spend all the time in aircon buildings and cars, doing flight training.