Once a time someone sent us a question to us, regarding if there is a more accurate simulation software than Moldflow. What we answered: if you share more info regarding the size of your part design, type of material to used, some cosmetic conditions that you will require, perhaps the number of pieces per year you need, and if an special face of your model is important, perhaps the brightness, or even a few key areas you would like to know what the diagnosis would be to investigate in your simulation, it would be good to know, please share a little more.
On the other hand I can recommend you also get to use alternative software as pre-processors to generate a mesh with good accuracy and get a good aspect ratio, and if you want to find a good representation of warpage, you can use FEM mesh like Altair Hypermesh or Ansys ICEM, good mesh generators and also used it for manufacturing processes, which can open in almost all software for fluids.
Just as well I would recommend you that any software you must verify first an structural analysis prior to validate your injection simulation to ensure you will not find bubbles, air trap and weld lines in areas of high or low strength. And also is very important to document the evidence you found, and take care later in a meeting with the tooling that will develop the tooling and take this into account in the development of possible new flow leaders, vents or put some specific flow to improve special parts of your model, don’t forget to invite, or call to your resin representative, because they have some tunning recommendations regarding final gate designs as well processing guide lines.