Ambrosia,
I’m no expert but here are a few thoughts and experiences I can share which you may find helpful.
I’ve been able to do padmasana from a young age since I learned it from my Mom (a yogini at the time). Despite this, I’ve never found it to be of any special help in meditation and I often meditate in half lotus if I’m feeling a bit tight after a long day in the office (hey, it happens). What I do find helpful in meditation is to sit in any position which is stable in which my spine stretches to to sky and my sit bones are firmly grounded - a position which allows me to meditate in peace. Some people I know sit on a zafu or blanket when sitting cross legged or in some form of lotus.
As many have said previously in this thread, lotus and half-lotus are based mainly on hip flexibility. I do a lot of hip openers in my practice because I find them extremely calming and liberating. In fact, sometimes I even fall to sleep at night in a form of Baddha Konasana.
There are a number of hip openers which I find helpful and may eventually help you stay in half-lotus pain-free for hours:
Ardha Matsyendrasana (Lord of the Fishes Pose)
Baddha Konasana (Bound Angle)
Janu Sirsasana (Head to Knee Forward Bend)
Virasana (Hero Pose)
If you don’t already, perhaps you can incorporate these deeper into your practice and be patient. Fill the bucket one drop at a time and don’t worry about when it will fill up.
One thing though. Some people have anatomical reasons why they can’t do certain poses in comfort, in this case the hips may be rooted too deeply to allow your hips to open the same way as some others.
Mainly men have deeper hip sockets, limiting their ability to do certain poses but sometimes women have this as well. For example, I’m a guy who can do these just fine but a good yogini friend of mine cannot (despite years of dedicated practice). Its OK because she is focused on being the pose, not trying to “achieve” something. We can all learn something from her.
So, if you find that (after further opening you hips) you are limited anatomically from doing lotus and half lotus much longer than you do now, focus on being the pose and be thankful for your life affirming practice.
Hope this helps.
Namaste,
Kiran