Hello,
Vivaldi is so prolific that it's hard to know where to start suggesting other works besides the 4 Seasons, but if you really like Vivaldi, then that's good news as there's plenty of good works to go round.
One of my favorite collections of concertos are the 12 concertos of Opus 3. Personally I enjoy these more than the 4 Seasons as every concerto is just as engaging as the next, especially RV 580 (Concerto for 4 violins) & 565:
Mvt. I of the latter, 565, contains one of the most unforgettable fugues in baroque repertoire I can think of and is a masterwork.
Although I wouldn't consider this as lively as his typical insturmental style, my favorite Vivaldi work has to be his Stabat Mater.
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The harmony and progressions in the 1st movement, Dolorosa, are surprising, complex, and very beautiful.
Anyway, so there's a couple of works I know really well, but any Vivaldi you find other than 4 Seasons and those I mentioned should not dissappoint you; his unique style can be found in just about anything he wrote, so just keep exploring and you should come across plenty to appreciate.
Take Care