Forget about Nikon D3300. Pentax K-50 or K-S2 are much better. I own two K-50 bodies with HD Pentax-DA 55-300mm F4-5.8 ED WR, SMC Pentax-DA 18-55mm F3.5-5.6 AL WR,
SMC 500mm f/4.5, SMC A 400mm f/5.6.
I love the K-50. 16 MP is plenty for starters. Spend much as money on better glass. Preferably full frame lens, so in the future it can be used with FF body like K-1 which I am
getting next month.
I shoot mostly with my manual focus lenses, even for my bird photography. There are tons of older good Pentax lenses.
Good quality lens last for a long time. Camera body can be change in the future and you still have the lenses.
I would go with K-50 and 18-135mm lens or just K-50 body only with older high quality FF prime lens. This way there is not a big investment in the camera body, but rather invest
in better lenses.
Here is a example what K-50 with older manual lens like SMC A 400mm f/5.6 can do.