The main reason for the slowness is the relays. As users grows the relays suffer, however more are being built as the community grows so just need to keep on top of them and make sure you add them to your account.

As for bugs, the clients are still under development but the devs do keep the development progress public and are generally very responsive which is great to see.

All perks of an open source network. There is power and transparency that you just wouldn't get elsewhere and is why i like it so much.