Here’s what one Nomad rider did to his great satisfaction, though I don’t know if you want to overhaul your setup this much: move two of those water bottles in the frame triangle to feed bags mounted on either side of the stem. The Decathlon feed bag, for example, is cheap, big enough to hold even a Nalgene, and durable enough to have lasted me over 20,000 km. (I guess the third bottle, if it is a mere backup, could go under the downtube.) Then, use the frame triangle for a frame bag, which really improves handling and comfort if you pack your heavier items there. The Ortlieb 6L frame bag doesn’t take up quite the entire triangle on my medium-sized Nomad Mk3 frame, so there is room underneath it to mount my pump on the top of the downtube.