I've never used Neutol Plus; however, another paper developer with similar environmental characteristics is Silvergrain Tektol. Actually, there are two versions -- Standard and Neutral. These are the next-generation commercial version of the mix-it-yourself DS-14 formula. I've used both of the Tektol versions and DS-14. They work a little bit more slowly than Dektol, but not much -- I develop most papers for 1:30 in Tektol/DS-14 vs. 1:15 in Dektol 1+2. That said, I've only developed a few sheets of Slavich Bromoportrait in Tektol -- certainly not enough to really get a good feel for the combination. I seem to recall the Slavich didn't take much longer to develop than the Agfa and Foma VC RC papers I normally use. In fact, I think my exposure times with the Slavich were longer than the development times; the Bromoportrait is a pretty slow paper.
If you're willing to mix developers yourself, there are lots of other options, too. I'm sure Tom's recipe will work fine, or you can mix DS-14, E-72, or lots of others. You might even experiment with the formulas Slavich provides, or come up with phenidone/ascorbic acid analogs of them.