First, congratulations on your new house! Second, I don't think your front garden is in decline as much as it's overgrown and somewhat weedy. I don't grow Hens & Chicks, but they look awfully crowded, which mean that they will eventually look dreadful. If you want IDs of your plants, I recommend that you post the pictures of the unknowns in the Name That Plant forum for quick and accurate answers.

There is a Cacti & Succulent forum here, which could help you with the Hens & Chicks, and a Northwestern Gardening forum, for help in what to do when; if someone there can't help you with when you should prune your roses - I do mine in April - then you could head over to the Roses forum.

I'm afraid that if you are smelling something rotten, accompanied by lots of flies, chances are that you've got a dead animal in there somethere; nothing smells quite like that (thank heavens).

Good luck with the garden, and with the future vegetable garden.

The comments you were given below your photos read as 'practical'.

For the azalea lacewing - the sooner you can spray the underside of those leaves with a neem oil brew, or similar, the sooner you'll stop egg production and help your azaleas to recover.

It may take several years before the evergreen azaleas change their leaves for fresh ones, however. I know Rhododendrons hold their leaves for several years before dropping them

The big 'elephant ear' plants are Bergenia and it takes a lot to faze them. They often have lovely autumn colour and pink or white flowers in spring.

If you don't want to move the lily - weed around it and topdress it with a couple of inches of bought compost. It may be a 'stargazer' type - in which case it will smell delicious. Asiatics are colourful but often scentless.

Agree about the stink in the garden. If such things as dead birds and mammals are unpleasant for you, and you find the remains - cover it with a generous shovelful of compost to keep the flies away and subdue the smell.

Roses and pruning. They look like shrub roses. Yes, you can cut them back hard, though they could take a while to recover. Or more lightly toward the end of winter, to take off the rosehips and any twiggy bits, leaving the big, strong stems. Maybe February in your area. Check at the local plant centre.

On roses - leave 'the last rose of summer' and the rose hips because that helps the rose to know to close down and harden up for winter. You can help by feeding it a high potash fertiliser in moderation.

Once you've pruned - give the plants a feed of blood and bone/dried steer manure and about an inch of well-ripened compost (store-bought if you're not yet making your own) before they come into leaf. You could also do the same for your azaleas before they come into bud but, perhaps, not the blood and bone.

Daphne odorata - you prune this by picking sprigs to put in vases, or using as sprays on your jacket, or treats for admiring friends. Within reason...:-)

Totally agree with your advisor where you posted your pics. ASAP get the tree seedlings out of the garden and any grasses.

I loved your Sempervivums. Just did. You might need to thin them out a little - and, as they flower, the individual rosettes will also die. Yet, so nice.

Thanks lisanti07028 and vetivert8, I've gotten a lot of feedback from a lot of people, including my local extension service, so my plan now is to process it all and get to work. I will try to post photo updates at some point. Thanks again!