Paw paws are tropical looking as well

How far outside of Philly are you? Most of Philly area is Zone 7.

Some plants to consider: Musa basjoo (hardy banana), Elephant Ears (Colocasia)---the bulbs will have to be protected in the late Fall, but grow FAST in season, Magnolias (if you have room for big trees), Yucca gloriosa,

You might also consider clumping bamboos (not the running kind).

If you really are a solid Zone 6, that is beyond the tolerance of true palms.

(7 being about the minimum zone for any success.)

For zone zone 6 it would have to be the most cold hardy if you looking at palms which would be Sabal minor 'Mccurtain' and Rhapidophyllum hystrix. Most windmill palms won't live in zone 6 long term, and if one rare one did happen to survive, it would look poor and and almost dead after any cold winter. They are really 7a/7b to 8a+ longterm palms. If anybody says different then they are making it up. Sabal minor 'Mccurtain' starts to leaf damage below about -5F to -10F but it can come back from the ground after about -10F to -20F when spring arrives. Rhapidophyllum hystrix starts to leaf damage below about -10 to -20 and perhaps could survive -30F to -35 if covered in snow and then come back from the small trunk in the spring. But the palms are not that cold hardy when young so protect for a few years until they get some size. A south facing wall would help alot as well.

I think treeguy's suggested temperatures for start of leaf damage to these hardy palms are even a bit optimistic. Siting, wind, and cold duration can affect the damage to palm fronds. Last season we hardly got below zero here in 7a, but the incredible duration (no winter warm-ups) and winds did a number on all my minors and trachys. Needles fared a bit better but still showed some cosmetic damage, depending on siting.

You may want to consider large-leaved tropicals used as annuals (or dug and stored), if you have the inclination -- plants like Elephant ears, bananas, castor beans, cannas, coleus, and smaller blooming annuals and foliage plants for a riot of color and variety of leaf shapes.

Or large-leaved deciduous hardy trees/shrubs. If you want hardy broad-leafed evergreens, you're going to be very limited in zone 6.

Everyone has a different idea of what 'tropical' means too. Some even consider Tree of Heaven to be rather tropical.

One way of getting tropical-looking foliage is coppicing. If you plant Paulownia and cut is down every year or so it will produce huge lush leaves. There are also plenty of big leaved hardy perennials, as Mackleya, sea kale or even rhubarb.

I'll second the recommendation for Paw Paw (Asimina triloba)

Great tree related to the tropical custard-apple, that has always looked tropical to me...something I DON'T like.

Also the catalpa (Catalpa speciosa) has huge leaves and flowers. Perhaps too messy for near a pool. Maybe smooth sumac (Rhus glabra)? Small leaves but looks tropical to me.

Hey, maybe we're overthinking this...what about plain old rhododendron and big leaf hydrangea?

I'm with subtropix on this one. Where, fairly exactly are you? The Scott Foundation has been growing Musa basjoo for ages. We had neighbors when we lived near Paoli that had an enormous evergreen magnolia. Most places near Philly fall firmly into the zone we call 'zone 6 that never goes below zero'. We lived there when those places went below zero, and the Inquirer had the news in headline type size that is usually reserved for things like the bombing of Pearl Harbor.

This is the first time I have had a chance to look at this post since yesterday and wow!! Thank you everyone for your help and many suggestions, I really have my homework cut out for me.

As for my exact location, I am about 45 minutes west of Philly in the Phoenixville area.

Sounds like where my mother was from. We could be relatives. LOL.

But getting back to the plants, it also depends on sun/heat exposure. How much sun and ambient heat does the pool area get? (More sun/heat not necessarily better by the way for some subtropicals.) I think if it were my pool, I would create the tropical effect by using some clumping bamboos in combination with hardy evergreens (Aucuba japonica, Laurels, trunking Yuccas, etc.), maybe supplemented with containerized palms for the season (which would require some protection over the winter). Containerized, I like Queens, Washingtonias, Mediterranean Fans, Butia/Pindo, and Dates (Phoenix). Good luck!

Musa basjoo will give you the most tropical feel with the least effort involved. An established clump could probably top out over 10 feet total height in 1 year though they might need heavy mulching for your zone 6 winters. If you're willing to wrap the stems and you guys get a milder witer, you could maybe get it to top 15-20 feet.

My bananas