Combination of arrowed list and boxes in tikzpicture

I am trying to make a figure showing some info using tikz. At first it looked OK, but after a while everything had moved so nothing was aligned. I figured that there probably is a much better way to do this, so that things cannot move around, but I have not been able to find a way to make such a list connected to boxes. Suggestions on how to make this in a better way is appreciated!

\documentclass[tikz,border=5]{standalone}
\usepackage{tikz}
\begin{document}
    \begin{tikzpicture}

    \node[draw, fit={(0,0)(7,1.2)}] (Meta)          at (3,0)    {Metaheuristic layer};

    \node[draw,align=left]          (Destruction)   at (0,-2)   {Destruction\\heuristics};
    \node[draw,align=left]          (Construction)  at (3,-2)   {Construction\\heuristics};
    \node[draw,align=left]          (Local)         at (6,-2)   {Local search\\heurstics};

    \node (toDestruction)   at (0,-.6){};
    \node (toLocal)         at (6,-.6){};

    \node (topDestruction)      at (-.5,-2.315){};
    \node (bottomDestruction)   at (-.5,-4.68){};
    \node (topConstruction)     at (2.5,-2.315){};
    \node (bottomConstruction)  at (2.5,-5.22){};
    \node (topLocal)            at (5.5,-2.315){};
    \node (bottomLocal)         at (5.5,-4.32){};

    \path[->, >=triangle 45, auto, semithick]
        (toDestruction) edge (Destruction)
        (Meta)          edge (Construction)
        (toLocal)       edge (Local);

    \path
        (topDestruction)    edge (bottomDestruction)
        (topConstruction)   edge (bottomConstruction)
        (topLocal)          edge (bottomLocal);

    \node[label=right:Remove K] (RemoveK)   at (-.3,-3){};
    \node[align=left] (RemoveKSR)   at (1.0,-3.8){Remove K\\same route};
    \node[align=left] (MakeK)       at (1.15,-4.78){Make K\\feasible gaps};

    \node[label=right:Fill the gap] (FTG)   at (2.7,-3){};
    \node[label=right:K-regret]     (Kreg)  at (2.7,-3.6){};
    \node[align=left] (Solomon) at (3.6,-4.3){Solomon\\insertion};
    \node[align=left] (GNN)     at (3.83,-5.5){Generalized\\nearest\\neighbour};

    \node[label=right:2-exchange] (2ex)     at (5.7,-3){};
    \node[label=right:2-interchange] (2in)  at (5.7,-3.6){};
    \node[label=right:Resequence]   (res)   at (5.7,-4.2){};

    \path[->]
        (-.5,-3)    edge (-.1,-3)
        (-.5,-3.6)  edge (-.1,-3.6)
        (-.5,-4.55) edge (-.1,-4.55)
        (2.5,-3)    edge (2.9,-3)
        (2.5,-3.6)  edge (2.9,-3.6)
        (2.5,-4.1)  edge (2.9,-4.1)
        (2.5,-5.1)  edge (2.9,-5.1)
        (5.5,-3)    edge (5.9,-3)
        (5.5,-3.6)  edge (5.9,-3.6)
        (5.5,-4.2)  edge (5.9,-4.2);

    \end{tikzpicture}
\end{document}