budget recommendation:
CYMA M14 this is a clone of the TM version and shoots fantastic out the box, can still be got for £150ish and you get shorter barrel version which will do CQB and out doors,
Pretty much any CYMA metal body AK.
Mid budget:
they are old now but Tokyo Marui P90 RD using MAG 170rd mid caps are a great platform for cqb and can hold their own in wood lands. you could also get a 5-7 as a side arm.
Tokyo Marui AUG something different. has take down function so you could swap out receivers/ barrels for different configurations. has progressive trigger or selector switch for semi/auto fire.
Top end:
Tokyo Marui Scar L Recoil is one of the cheaper of the recoil but has all of the functionality of the newer models.
for shits and giggles tokyo Marui AA-12 with a drum mag. Full auto, triple barrel shotgun with recoil. whats not to love?