600W HPS lights are going to crank out some light and are great for flowering. You have a lot of grow space, so maybe they won’t cover it all, but a 600W HPS will cover probably 1 to 1.5 square meters of space.
People on this site really like the HLG quantum boards. They are expensive, but the trade off is that they are efficient and will offset the initial cost with lower electricity bills. They come in different spectrums for veg and flowering.