The ECHELON-1 trial showed improved PFS and OS in patients with stage III and IV disease treated with A-AVD compared to ABVD. In addition the A-AVD allows you to avoid bleomycin as you said. So A-AVD is certainly worth considering. My only concern with that regimen would be the peripheral neuropathy which could be problematic in an older patient. In my experience the majority of patients will get peripheral neuropathy with A-AVD and in some cases it can be pretty severe. Notably, the results of the SWOG S1826 trial comparing A-AVD to Nivo-AVD were just recently reported at ASCO and showed that Nivo-AVD had better 1 year PFS (94% vs 86%), although this is admittedly short follow up. This also avoids the risk of peripheral neuropathy from the brentuximab vedotin and pulmonary toxicity from bleomycin. Therefore, Nivo-AVD would be worth considering in your patient.