I find hammocks more comfortable, but there is no real weight savings by using a hammock. You don't need flat smooth ground to set up a hammock, but you do need something to hang the hammock from. Developed campsites don't always have good spots to hang. On the other hand if dry camping, it can be nice to not hunt for the ideal site to set up a tent. If camping with others and sharing supplies, a tent will save space and weight. I agree a good sleeping pad is probably going to be the most important part of your kit. When using a hammock, you'll need either a sleeping pad or an underquilt. I'd avoid buying a single wall tent because they're prone to condensation issues if you're not careful.
Whatever you buy, I'd be mindful of how mosquitoes can ruin a night's sleep. You can save lots of cash by purchasing a no name tent or hammock off of Amazon if your conscience allows, but you want to be sure you get something that is decent and will keep the mosquitoes out.