Buying parts too soon is the worst thing you can do, and will cost you much more down the road.I've decided to start to buy some of the parts, but I'm wondering if this Design would be good/strong enough,
Everyone asks if their design is "good enough". The problem, is that everyone's expectations are different. What's good enough for some, may be totally unacceptable to others. You really can't build a machine that's too rigid. The better you build it, the more acceptable it will be to you. Budget always comes into play.
You want to be sure you get screws with 10mm pitch. The common 5mm pitch screws are a poor choice for a router. 2010 screws are probably the best choice.
3D printed parts are just not strong enough imo for a machine of this size. Look at all the builds on this forum, and you won't find any machines using 3D printed parts like that.
What drives do you plan on using?
Is that a single linear rail for the Z axis? If so, that's not going to work well.