You mention bullet connectors, but show an image of spade/quick connect terminals. I hate bullet connectors, but never really had a problem with quick connect - although I rarely do in-line connections with them, almost always wire-to-board with PCB mounted terminals.
Yes, ebay, amazon, aliexpress is flooded with "cheap" terminals, and crimping tools. As with most items on these sites, they're not necessarily "bad" but its pot luck whether or not you get a decent one. For applications where its important, get branded terminals from reputable sources.
Don't solder crimp connections, its unecessary and can compromise the mechanical properties of the stranded wire, making it more likely to break where it flexes. If you want to splice using solder, then solder. If you want to splice using crimp, then crimp.
Are you asking about other types of connectors for in-line connections? Or are you splicing and want to know the best butt terminal, or crimp splice? Or are you after a relaiable and decent crimping tool for the terminals you pictured? It isn't completely clear what you're after.