Drafts save reliably. Asking for a suggested reply, or a new one in a different tone, now keeps the draft with the lead so it is there when you come back. Until this fix, a new draft could fail to save.
Every plan states its allowance. Free includes 3 AI reply drafts a month, Pro 300 and Growth 1,000. Each draft is written fresh for the thread in front of you, so it is a real cost to us, and a stated allowance is fairer than "unlimited" with limits nobody could see. When you reach it, the message says which plan includes more.
You are told when a draft cannot be written. If drafting is briefly unavailable, you now see a message saying so, instead of nothing happening, and the attempt does not count against your allowance.