First choice: stencil. Stainless steel stencils are cheap these days and fantastic. No good for rework, though. Second choice: manual syringe. As you've notice

First choice: stencil. Stainless steel stencils are cheap these days and fantastic. No good for rework, though. Second choice: manual syringe. As you've noticed, it's difficult. Some pastes are thixotropic, so shaking the tube before dispensing can help a little. Or maybe that's just my imagination. Third choice: stick a stainless steel pick or even just a toothpick into a little pile of paste and dispense it by hand. This is surprisingly useful for those really fine-pitch pads... but it's tedious.