I recommend looking at as many tanks as possible lol. what about seiryu stone or a mix of the two? I agree its difficult making a plant look like a focal point... without it looking odd anyway.
If you have like a mountain path kind of effect, on one side you've got the majority of plants and hardscape at the back, with your HC at the front, then a gap between the hardscape and plants, and then your favourite plant and maybe some redmoor or stone of some sort so it doesn't look too lonely.
If you have like a mountain path kind of effect, on one side you've got the majority of plants and hardscape at the back, with your HC at the front, then a gap between the hardscape and plants, and then your favourite plant and maybe some redmoor or stone of some sort so it doesn't look too lonely.