Answer: There are many fragrant lilacs to pick from, and some of them do have deep purple blooms. In my experience, it is best to shop for lilacs (and roses) in person so you can see and smell them for yourself and not rely on the catalog descriptions or someone else's opinion of what is "deep purple" as opposed to say, "violet" and which fragrance is "best" since we all have a different sense of smell. In terms of size, those huge overgrown lilacs could benefit from a regular pruning routine. Correct annual pruning will keep lilac at a manageable size so those tall trunks never develop. A quick web search using "+syringa +purple" as your search term should yield many examples.
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