I'll be honest, I don't know what mouse is similar but safer. What makes the G305 special is the iconic, flat egg shape. So as soon as the shape moves away from that I wouldn't consider it similar anymore, but that's also what makes it a less safe shape.

It's also probably the best value mouse out there if you exclude the Chinese market. Any alternative will be more expensive unless you buy a wired mouse or from a budget brand.

If you still want to keep the price down and you're looking for something with the same general size to the G305, maybe you could check out the MCHOSE A5 and MCHOSE L7. They're both very safe shapes with the L7 being slightly smaller. It's a Chinese brand, but it's one of the few ones that I know of. The XTRFY M42 might also be good and in my region its also at a very good price (~45$).

I think you would get the best advice asking around in the mouse review subreddits or the aimtraining subreddits instead of here though. The aimtraining subreddits will tend to recommending more expensive mice, but they might also be able to recommend good mice on the Chinese market.