re: Budget airlines to Europe

Try Turkish. TAP is a mainstream airline (I've never flown, I take Lufthansa, United or Turkish out of IAH) but has a lot of great deals.

Look for different departing airports, and be willing to move your dates a couple of days in each direction. The biggest budget killer is a lack of flexibility. Can you fly into Brussels instead of Paris? London and take the train to Paris? Arrive on Tuesday instead of Friday? etc.
As always, use ITA:
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