Weeping willows are more romantic, IMO. But they get jolly big.
I had an entire lilac hedge - it grew to about 10' tall, mixture of paler and darker purples. My parents have a white lilac, about 12' tall.
We always brought it into the house, never heard of it being unlucky to do so, but Yew - never (we had one of those as well).
I don't recommend white lilac because the florets start to go brown as they age and it looks worse on the white lilac than on the purples.
They don't take well to pruning either, as the flowers grow on new wood - so if you prune the new growth off, you don't get many flowers.
Buddleia provides a similar flower, beautiful scent, can grow to 10' in one season, attracts butterflies (and bees), and can be chopped right back to about 6-12" high after every growth. Also comes in many shades of purple, white - and yellows and oranges, iirc. I'd go for the buddleia over the lilac, even though it's more of a shrub than a tree.