I agree Brifters are made to work vertically oriented, on drop bars..
You can Hybridize your bike sell the brifters, to help fund the other levers for straight bars..
Mustache bars with simple road brake levers , and bar end shifters are another way to go..
door #3 Trekking bars 22.2 tube figure 8 bend , hand position variety.. [Mine are set up higher than my saddle..]
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