Meaning primarily expository articles aimed at a wideranging mathematical audience, at the same technical level. But not by such a predatory publisher.

4$\begingroup$ "The journal does not consider papers of expository nature " $\endgroup$ – Francesco Polizzi Jul 8 at 21:18

2$\begingroup$ See mathoverflow.net/questions/15366/… $\endgroup$ – Tom Leinster Jul 8 at 22:20

1$\begingroup$ for the sake of fairness and precision, the term predatory publisher has the specific meaning of a publisher that "charges publication fees to authors without checking articles for quality and legitimacy and without providing the other editorial and publishing services that legitimate academic journals provide". This does not apply to Expositiones Mathematicae, does it? $\endgroup$ – Carlo Beenakker Jul 9 at 7:44

1$\begingroup$ The MO question Which journals publish expository work? is probably the most useful resource on the web for mathematicians seeking an answer to that question. Can I suggest that people add their answers to that question rather than here? Then all the information is kept in one place. $\endgroup$ – Tom Leinster Jul 9 at 10:08

1$\begingroup$ Carlo, many people use "predatory" for Elsevier, with some justification: they prey on academia and would die without us. The Wikipedia definition is arguably too narrow. (Plus, see the section "Bohannon's experiment" of the Wikipedia page, which shows Elsevier behaving exactly according to that defn of predatory publisher.) I think for Elsevier, parasitic is even more apt: they suck out as much of universities' blood as they can while still leaving us alive. $\endgroup$ – Tom Leinster Jul 9 at 10:17
You can try l'Enseignement MathÃ©matique, published by the European Mathematical Society.

2$\begingroup$ Pete Clark's experience with EM may be worth bearing in mind: see point 2 in his question mathoverflow.net/questions/15366/… $\endgroup$ – Tom Leinster Jul 8 at 22:22

1$\begingroup$ ...and Felipe Voloch's answer to Pete Clark's question: mathoverflow.net/a/15404 $\endgroup$ – Tom Leinster Jul 8 at 22:24
Some journals publishing only surveys: Bulletin of the American Mathematical Society, Sugaku Expositions, Russian Mathematical Surveys. Some journals also publish surveys besides research articles.