When I shot slides, I used Transpacolor and Peak Imaging, both very good but never perfect as no lab is perfect. Transpacolor were superb at getting a print from a slide, by the way. If either of these are the labs you tried then it is either bad luck or a sign of the times. Try them and then if you are not happy you should buy a Plustek scanner or similar and get control. Scanners are not considered 'analogue' on this site, unfortunately.

For colour neg, I like Photo Express as Mr Rusty says, very very quick and quality is good. Ag are very slow, good quality. Peak are famous for quality but very expensive, especially a CD with P and P. Photoexpress should start doing 120 if not slides, IMO.