Failing elderly pine trees how to help?

I moved last fall into a circa 1955 suburban ranch with a well-treed lot. I have one oak, 2 huge locust trees, one holly, a white pine, a blue spruce, 2 clumps of birch, & a huge pine tree (not sure what cultivar). The home was also practically encased in yew, a few arborvitae, some boxwood, and 4 viburnum. The viburnum were blocking some windows & had actually reached over the gutters, & had to be removed. Most of the yews were removed. Two arborvitae were dead from obvious bagworms, & I also had those removed. My problem is with the blue spruce and the pine tree. They have many dead branches, the limbs droop, and the pine tree, despite producing a good quantity of cones on the upper half of the tree, is getting brown at the bottom branches. I am pretty sure that the last two owners weren't keen on gardening or landscaping. An elderly neighbor says the trees were planted at the time the house was built. One more issue: the pine & spruce are close to the remaining trunk of an old crabapple tree that I also had to have removed last fall. The crab was obviously dying &, in fact, the trunk turned out to be abt 80% hollowed out. I left abt three feet of the trunk standing, thinking I'd put some concrete in the bottom & use the top to anchor a birdbath or shove some anuuels in, but I've been too busy fighting off the deer so far. I did see one bag of bagworms on a nearby small tree early in spring & used the Dawn method of removal (soap hand or dish gloves with dawn & slide them down over the bagworms, & then discarding them in a sealed baggie). How do I further diagnose and tret my pine & spruce? I don't want to lose them!

First question is do you live on a street called "Love canal"? Did you have any equiptment (Heavy) when the clearing took place? What is the soil type and what type of weather has been going on? Any drought? Pine trees when stressed send out lots of cones. What are the needles looking like. Lots of needle drop?

Thanks for your reply. No "Love Canal" that I know of. A hundred years ago it was part of a large farm. No shooting ranges or mega contaminants that I know of. Plus several neighbors also have trees of similar size & while one nearby pine has a lot of dead branches on one side, the rest of it seems in great shape. Re: clearing equipment: the crabapple was downed with a chainsaw & then chipped on site. Then the area between the pine & the spruce was cultivated VERY shallowly with a minitiller & we put down a mixture of compost & mulch.
The bushes were all removed (even the man-eating viburnum) by one strong man with a pickaxe, & then chipped.
Uh-oh, I just remembered something. The viburnum were removed last fall & then dragged to a spot between the pine & spruce. They stayed there all winter until we finished bush removing & then got chipped with a whole lot of stuff on Chipper Day this spring.
I don't see any noticeable needle drop. The bark looks in pretty good condition. This is an area where the deer have a path to their favorite fence- jumping spot. I see their hoof prints clearly, & sometimes run into them personally. The soil type is (sigh) heavy clay. I'm in zone 6a. I think what bothers me the most is that they seem browner & droopier than when I first saw them last year when I was getting everything inspected to buy the house.

Ok it is clear what the problem is. They don't like you. Ha Ha Ha. Any way You haven't done much but cover the roots with the viburnum piles. I would look closely at the one that is bad on the one side and play dick tracy what is different on the tree (parasites, fungus) and what is different on the root side on that side. Then look at the bark for sawdust at the base and sap running out of it. Bark Beetle. Then consider any chemicals you put on the lawn, in the septic system, and what is running down any hills around. (neighbors and county chemicals.) Has there been any changes up slope with any development that may have affected the ground water flow. Come on Be a detective and think what was and what is now. How is that different?

You wrote: "Ok it is clear what the problem is. They don't like you."
ROTFLLOL! Or should it be Rolling on the ground for gardening forums? In any case, I laughed out loud since that is my first and often last thought abt gardening failures. It just doesn't like me!
OK, I will inspect tomorrow, checking bark, needles, looking for sap or sawdust or critters of the insect variety. Thanks for the suggestions!

BTW, here is a picture of the viburnum before removal.

Oh you have courage I could not have eliminated those. Maybe one or two and a good pruning. But a garden needs to change to fit the desires of each owner. Good work! I used to think that plants didn't like me so I learned how to make them happy. I'm codependent and like to make everyone happy and it works for plants. (Not for people) Soil ammendment makes plants love you in a very clear way. ADD COMPOST, ADD COMPOST........

The only reason I had them taken out was that my bedroom window was behind all of that--- plus the fact that there was only abt 3 inches of greenery on the tips: the interior was mostly bare branches. It was a choice to live without any view of the outside, or haul them out & renovate. It's good to know that plants respond well to a codependent approach. I can do that. (I can MEET your needs! I can give you compost! I'll get rid of those nasty weeds! I'll get you some worms even!) Thanks again!