Lucky you, bitbit!
Well, I'm in the south so I can't comment on Michigan weather but here are some of my thoughts...
The Colocasias would probably do well near your downspout but they do get larger so space might be an issue. One thing nice about the Colocasias is that after the first frost, you can dig up the roots and easily store them over winter to plant out again next year.
Salvias are good for the pollinators: bee, butterflies, and hummingbirds. 'Black and Blue' might get too big for your small garden but is really pretty and bees and hummingbirds love it. It is a perennial that spreads like mint here, but it would get killed in winter in Michigan so the spreading wouldn't be an issue. Like the Colocasias, after the first frost, you can dig up the roots of 'Black and Blue' and store them over winter to plant out again next year. S. farnicea 'Evolution' would grow in the sunnier areas and is attractive to bees. Salvias coccinea 'Lady in Red' and 'Forest Fire' are attractive to bees and hummingbirds, with 'Lady in Red' being a hummingbird gardeners traditional favorite. They will grow in sun to partial shade, and produce seeds easily. However, the price on those is a little steep considering that they are so easy to grow from seed or can sometimes be purchased in 6-packs for a couple of bucks.
Begonias take shade to part sun, but won't take standing water. They also make nice hanging basket/container plants. The 'Dragon Wing' Begonias are very versatile, pretty and easy to grow taking sun to shade. They are easy to overwinter as houseplants.
I like Abutilons a lot and they should grow in your conditions (not the soggy spot,) but I haven't grown those specific cultivars before and am not sure how floriferous they would be for you. Can also be overwintered as houseplants.
The Coleus should do well but make sure you choose the sun-tolerant ones for the sunny areas. Bees like the flowers when they bloom, but most gardeners don't and pinch them off. (The flowers look like Basil flowers.) The Plectranthus would be similar. Easy to root in water.
'Silver Falls' Dichondra should like your garden and is a really pretty annual ground-cover and looks gorgeous spilling out of containers and hanging baskets. You can collect seeds from it, if you know what to look for. The flowers are so insignificant that it's easy to miss the seed-pods unless you are watching for them.
Those Euphorbias should do well since they are tough and take a variety of conditions. They are very floriferous but I've not noticed any pollinators on mine and they haven't set seed. They are supposed to be easy to root in water if you want more.
Fuchsias might work for you but they hate the weather here, so someone else will have to give you advice on those.
Geraniums should work in the sunnier areas. Hummingbirds will use some of the single-flowered varieties. Like Jennifer said, easy to overwinter as a houseplant.
I've not grown those Lophospermum vines, but that's probably something I'd pick to try. Sounds like it might work for your conditions and pollinators. Also since it can be trellised against the wall, it would take up less space.
'Persian Shield' Strobilanthus does well here in a variety of conditions and is very pretty. Rarely flowers though. It is more purple in the shade and more silvery in the sun.
Torenias are nice low-growing annuals for shady areas.
I agree with Jennifer not to bother with the double Impatiens walleriana due to the downy mildew problem. However, the Sunpatiens would do well for you, I bet, and are resistant to the mildew. I didn't notice pollinator activity on mine though and they don't set seed. Another one for rooting in a cup of water.
I've not actually grown Heliotrope but that might be fun to grow in a pot near your door so you could take a whiff whenever you pass by. They do smell lovely.
Goodness, I do go on, don't I...
So, has anything in particular on the website caught your eye?
